It is fair if you compare Apple with other manufacturers, but it is still unfair in absolute terms. The hardware still works, and the work they're doing to support other models would let macOS work on that laptop as well, as proven by tools that let you do the upgrade unofficially.
Eh, with prebuilt PCs it’s muddy because the bulk of heavy lifting is done by Microsoft, not the manufacturer. It’s not unusual at all to pull up the firmware/drivers/etc page for a random laptop and find that updates stopped rolling out about 2 years after its introduction to the market, despite Reddit and similar being filled with reports of firmware bugs for that particular model.
Fair point, but I think the lack of those updates impacts the average consumer much less than lack of OS updates.