I'm 3 years in and have never needed servicing. If I do, I'm fine having to go back to Apple. It's not a good fit for everyone. But it is for my niche. (Also, Apple stand out in having long first-party support runways for their products.)
It's not bad to want to pull apart and service your own laptop, but for me it's a tool to get a job done and if it breaks I'll send it to Apple to fix
My previous Intel Retina MBP lasted from 2012 to 2020, and now my dad uses it because it still works fine. My younger brother uses my ~2008 17" MacBook Pro (it only runs on wall power, though). Repairability has just never been much of a concern in my use of Apple stuff
I never had a laptop for that long before. And just had to replace the battery once, by an after market one. The keys on the keyboard disappearing is the only notable aging symptom.
Maybe an outlier, but based on that, I'm confident the M1 may last long too.
otoh i hope to be burried with my m1 airbook (for home use) -- i hope never to buy another notebook class device, and just keep replacing the battery every 5 yrs.