Google maps was still years away. And tile server tech wasn’t quite there to ship it yet. But it was the obvious thing to build, and not in any way a mystery as to how you’d do it.
Inventions are often that way -- think of the mousetrap. People knew springs pinched the crap out of you when released. But nobody had made a device to kill mice, yet untilthat was invented.
I don't know what the cognitive bias for thinking that because you thought of an idea it must be obvious is, but it exists. I say that as a patent inventor.
The technical "how" of the implementation is not really obvious, you could implement the same result in many possible ways, some better than others.
That physics combination with drag and drop interaction was not obvious in the time period we are discussing. The closest thing I can remember to that sort of thing were side scrolling games that accelerated with the character centered on the screen according to the game's physics, and possibly paddle-based game physics dating to the Atari era.
Slowly increasing scroll was present in some interfaces. But not tweened stop.
My main point is that clever people often dismiss what they find trivial to be obvious to others, and while that's often the case once many examples have been observed, it isn't prior to the exposure to many examples.
Copying natural laws in our work is something that was obvious for humans for millennia. We've been imagining space ships 100 years before going to space but simulating inertia for an object "sliding" on a screen was "not obvious at the time"?
Of course it was! How to do it (well) may not have been obvious but the idea of doing it was there for anyone using a computer. The parallel with the real world was always obvious because this is directly analogous to how physical objects behave and you'd do naturally in the physical world. The world around you provides the "observed example", not other computer implementations.
I personally thought since decades ago about this kind of inertia while scrolling through lists or dragging things. I thought of transparency, skeuomorphism, writing on touchscreens, etc. long before they were implemented because computers could handle them. And I can assure you I wasn't the only one.
"Same thing that you've been doing for ages in real life but now on a computer".
P.S. I'm thinking of a holographic/VR 3D interface right now that replicates interactions with physical objects either by manipulating it with my body parts, with electronic input devices, or with a BCI. I hope I live long enough to read an internet discussion where someone claims this was just not obvious back in the dark ages of the early 2020s...
