To be fair, I’ve had no problems with Catalina either - other than the niggle that it took some hacking to get it onto my 2009 Mac Pro. The specification says ‘Go’ but Apple artificially says ‘No’. I get that they want to sell me a new computer, and 11 years of being up to date is pretty good run, but until they make an affordable version of the Mac Pro (sub £2k) that I can update to give it a similarly long life span, I ain’t buyin’. That said, Catalina has run without problem on my old beast.
As to replacing batteries, well true. Officially you can’t replace the battery - but, unofficially, in my experience, it’s a doddle. A few screws and the top (okay, bottom) was popped off of my MacBook Air, the battery came out easily and the new (NewerTech) one went in without trouble. All in all the work of a few minutes. Hardly onerous. And, actually, it’s so nicely assembled that it was a quicker job than relacing the battery (also fixed in place) in a friend’s Asus Zenbook.
The battery in my ThinkPad is ever easier of course - one sliding clip and off it pops - but it’s heavier, bulkier, and not as nice to use. So, for all the inconvenience of a few minutes every five years to replace the battery, I’ll go with the Apple. But you choose the tool that works best for you. No point in coming over all religious about it.