The instinct seems to be that they want hinges in their code, so their code can adapt and be reusable between projects. But they don't actually know where the hinges should go, because they don't need them yet. So they just put hinges all over the place - even where hinges aren't useful. If the metaphor is confusing, I'm talking about things like making an interface around a class, when there's only one implementor of that interface anyway. Or breaking a complex function into small, "reusable" pieces spread over multiple files - except where those small pieces are only ever used by that one call stack anyway. (And where they aren't that semantically self contained.) The result is harder to follow code with no actual benefit. And the resulting code is almost always bigger and more complex, and thus harder to work with.
Usually code thats the easiest to refactor is code thats the easiest to understand. That means, small, dense, correct code, with a simple test suite. If you write code knowing that you can (and will refactor) later anyway, the result is almost always better software. You will come up with a better design after you know more about your problem domain. Plan for that, and set yourself up to take advantage of that knowledge later.
I don't see this as bad. Modularization protects against an uncertain future. Most code that's modularized is only used once and this Looks bad only because you haven't seen the alternative of what could have happened if code wasn't modularized.
Non modularized code is often designed wrong because of an uncertain future. Once the project is too far down the line, people just keep piling technical debt on top of the design flaw. Code is rarely rewritten until it's at a point where it's horrible than it takes a massive engineering effort to rewrite and even this rewrite could be wrong.
The alternative is code littered with modules that are used once. Which is better? Obviously the more modular code.
This is your problem, right here. Your instincts know when refractors and rewrites are appropriate. But if you live in a corporate culture where those things are never allowed to happen, of course you’re going to run into problems. Premature modularity is a poor man’s substitute for simple-then-refactor. It’s not a good process.
More likely you think it's a bad thing because your code isn't actually modular. Likely you need one piece of logic but that logic isn't modular so to move it to another location you need to drag a bunch of extra baggage around with it. You wanted a banana but instead you got the gorilla holding the banana and the entire jungle. Sound familiar?
The smallest primitive that is modular is a pure immutable function. If the modules you are moving around are not pure functions then likely your code isn't actually modular.
For it to be truly modular, you also need to be able to use it in multiple contexts. I could take any random 5 lines of a complex function and pull it out into another function in another file, but that doesn't guarantee that this was a smart thing to do in that particular scenario. What I'm saying is there are tons of times when people do this merely to get the linter to pass, instead of for the actual purpose of modularization.
If A and B are coupled so tightly that one cannot exist without the other, you don't really have two modules. You have one, AB. This is a common problem with improper application of the idea of modularity as well as OO concepts (in particular, breaking things into classes and thinking it creates a module). The latter is particularly pernicious in languages which don't have a clear separation between classes and modules (Java, for instance, or historically I think this has changed).
The reality is that there are two (at least) kinds of modularity. "Syntactic" (I need a better name for this) modularity like Java classes, or C's translation units (why I need a better name). These act as modules, but don't necessarily define a real, proper module. And then there are your real modules which are comprised of the things that must exist together (like in the earlier example), regardless of the project structure or language's notion of a module.
I had a team try to convince me their code was "modular" but their GUI portion was directly tied to the DB portion and other logic. Nothing could be instantiated separately, so it wasn't really modular, it was just using the language and build system's notions of modules to create the illusion of modularity (C++ and VS in their case). In contrast, another team had developed a collection of libraries (C# and VS again) that were used in multiple applications. That was real modularity.
Modular code involves writing code independent of context. One way of doing this is to wrap every expression in a pure functional context. Another way is to make every variable immutable.
> I could take any random 5 lines of a complex function and pull it out into another function in another file, but that doesn't guarantee that this was a smart thing to do in that particular scenario.
Doing this doesn't hurt. There's nothing stupid about it unless you coded everything in a way where it's NOT modular. Procedural programming is usually not modular because the results of a computation depend on the Order of the procedures. Immutable state is isomorphic to an expression so procedural code with immutable state solves the issue.
Let's say I need a function to add 3 numbers. I impliment it like this:
addThree = func(x, y, z){ return addTwo(x, y) + z}
addTwo = func(x, y) {return x + y}
I understand why you think that type of modularity is bad, but it is actually good. It only appears bad because most of the "modularized" code is only used once.
No one can predict the future so the way to minimize rewrites is to make composable units of code that are small and highly modular. It's not about breaking up your code. It's about writing small logical component then building up the larger component by composing the smaller components.
This results in a large number of modules that are only used one time, but it prepares your code for the inevitable point of the future where you find out the design was wrong and you have to rearrange the logic.
When such a time comes you most likely just trivially rearrange some of your logic and add additional pure functions into your pipe line for any actual new logic. The majority of your modules remain untouched and this only seems bad, but it prevented a rewrite of the entire framework.
The timeline where the definitively worse outcome occured didn't happen because your code was too modular. So you have no point of comparison and you assume the modular code that is hard to read is bad only because it's hard to read. You failed to see how it prevented a massive refactor.
Usually if code is so unmodular, people just live with it and keep accumulating massive tech debt on top of everything. If all your seeing is tiny functions everywhere then this is definitively better than the alternative.
From a design perspective highly modular code is always better. From readability perspective though, you are right, modular code is harder to read. But there are ways to mitigate this.