You have a larger n than I do, but still I am surprised that they would wipe out after a year.
I readily admit that I might just have been extremely unlucky, I don't know. I really didn't like having to throw headphones away just because they simply wouldn't turn on anymore so I'm just very wary of spending money on these headphones right now, especially since Sony WM-1000s are hovering at a similar price point and my experience with those has been very positive: almost 3 years in now and the pair of mk2s I have works perfectly.
If the battery was replaceable, even by professionals, I'd be far more likely to consider getting a new pair just because I miss them... and really, It's kind of a shame because the form factor and general operation of AirPods is really lovely, in my opinion. I was at first ready to be disappointed because they looked very similar to the wired ones Apple used to include with their devices which were awful, but I was very positively surprised.
I have a pair of airpods I got with my new job. Within a year they lasted less than 2h and never even at the start lasted longer than 3h. When playing D&D with friends I had to use one at a time and rotate them out to last the whole session.
Are they small? Yes. I don't expect INCREDIBLE battery out of them. But my wife has a pair of Bose equivalent and they last like 6h a day on a single charge and continue to do so 3 years later. They are slightly larger which accounts for longer initial charge but the degredation on my airpods was stunningly bad. I ended up having to replace them this year (1.5y later) for a new set because they were no longer capable of supporting my work meeting schedule.