It was still in official support at that time but I got burned by my first android phone going EOL within 6 months of when I bought it and I wasn't going to leap again without knowing there were actually ROMs that worked without major feature loss.
That previous phone (Moto G Falcon) had a bunch of custom ROM issues too. Eventually I found one that worked OK but that's just not acceptable to have a glitchy third-party build where some random shit doesn't work less than 6 months after purchase.
Try running the Samsung S23 ROM on a Nokia 7 plus and tell me how it goes: that's the same problem.
I have been using /e/ OS on a Fairphone for 2 years, and it is absolutely great. I just use it like a normal Android, no need to fiddle with it _at all_. Some apps don't work because I'm de-Googled (no Play Services), but you don't need that (or you can accept that some apps don't work).
One week, apps started throwing an uncaught null pointer exception on startup because their network permission was revoked.
Even without that, random apps (especially for charging EVs and parking, and especially if it was raining) would just plain break for a few weeks, then start working again.
It would be nice if there was a commonly-used android compatibility suite for developers (of apps and of roms), but there isn’t, so everything is flaky once you are slightly off the beaten path.