It's like a faith amongst some people that this is bad, but the idea seems to lack evidence.
There will always be some non-zero number of people who either want or are genuinely best-served by something like the entry-level Mac mini, but that doesn't equate to it being a generally-good option.
lol
I don't see what iPads have to do with this at all. Surely tablet vs desktop is an entirely different decision.
As I'm sure you know, there are many articles, threads, et. al. out there about whether 8GB is enough for a Mac. We can link articles back and forth all day, but here's what it comes down to: with only 8GB of RAM, even light use will see the Mac offload to swap much more often than if it had 16GB to work with, and one of the first "scandals" that arose from the M1 Macs was that bytes written to the internal SSD was much, much higher than it should have been, because of that swap usage.