I have many 2015 MacBook Pro's. All tour. All are almost permanently on. I replaced the battery on two machines last year. Speakers fine. Screen fine. Are you implying the relatively young M1 Air is so badly made, the speakers, monitors, AND battery have already needed to be replaced?
> my lifestyle involves very rough handling of the machine
No, it's not badly made, GP seems to be a huge exception. Please, read the full comment...
My M1 Air has been around since launch, have traveled with it just throwing inside bags, dropped a few times, sat on, etc., it still works 100% fine without any part swap, and looks almost pristine with just a tiny scratch on one of the edges from a drop.
As for the battery, yeah ideally it'd last longer. But it's seen a lot of physical abuse, tons of full charge cycles, and generally wonked out charging setups so I can't get too upset.
For the monitor I'm honestly surprised it lasted as long as it did. It had been slammed around and crushed far more than what it should be able to take.
And how are you saying you've had M1 devices for 6 years? I don't think thats possible.
[1]: https://www.ifixit.com/products/macbook-air-13-a2337-late-20...