Earlier quoted context omitted.
OS LTS support barely matters when planned obsolescence is baked in at the hardware level. Wearing parts (eg. SSD) are soldered on newer macs and there's intensive efforts to make sure even if you have the tools you can't repair it. Parts aren't available but if you get your hands on there's cryptographic parts pairing so it more or less can't be replaced: https://rossmanngroup.com/services/ssd-data-recovery/macbook.…
My MacBook Pro M1 is 5 years old now and the SSD wear level is at 4%. SSD wear is not a problem for normal users. Meanwhile Apple's standard OS support period is 7 years, that's a much more imminent limit. Not saying that I support non-user-replaceable SSDs, but if your goal is reducing e-waste, there are more impactful changes to make.
I'm not saying that I support closed-source firmware, locked bootloaders, or even that replacing SSDs is the one true path to sustainability.
I believe it's a whole field and we shouldn't tolerate compromises on any level. It should be 100% illegal in any civilized country to sell the kind of lame hardware we have today. It should be 100% repairable, 100% open bootloader & free firmware, 100% public tech docs/datasheets. Original manufacturer OS support is not insignificant, but i believe it's only significant because we have so little control/understanding of the hardware/software stack.