With 40 years of Apple development under my belt, I can safely say that Apple used to be great about supporting older hardware.

When they were on rough times, everyone understood about needing to break compatibility with old hardware (that nobody really cared about anyway because, despite it's horrendous price, was super obsolete due to the rate of Moore's law back then). But nowadays, Apple is invalidating old hardware platforms for superfluous reasons, like abandoning 32-bit apps, enforcing their OEM cryptographic authority (with T2 chip) and getting into it with nVidia (granted nVidia screwed up big time with those GPU chips that blow) or more recently, getting into it with Intel (which has caused agonizing supply-chain issues for Apple). They are no longer that good about helping people support Linux either --you would think that when they deprecate a machine, they would at least have the decency to open source all of its drivers...(and have pre-negotiated the legal rights to do so).