The keyboard issues were really jarring precisely because Apple had, up to that point, a really great reliability reputation - in my experience, on par with the super-overengineered late-90s ThinkPads (IBM, not Lenovo).
I retired several PowerBooks and MacBooks at 6 or 7 years old that were still physically fine, but no longer appealing to use for Moore's Law reasons.
My wife's using my old 6 year old 13" Pro, and while I now find the keyboard weird, it's utterly capable of anything she needs to do with it -- which is pretty much a regular human duty cycle (ie, she's not running virtual servers on it like I was in its initial life).
We then passed on the small Air she'd been using for like 8 years; it's in daily use at a friend's house now as a spare platform (which turned out to be a big deal, given quarantine). My guess is that Intel Macs are about to hit a gate with the shift to ARM, and you won't be able to get 8 years out of one purchased in 2020, but I could be wrong about that. (I mean, I definitely am if you have relatively simple needs -- even if you get stuck at the last rev of Intel-friendly OS X, there's software for you there that will keep working.)