Couldn't you just upgrade yourself in the pre Apple silicone days?

Like within minutes, with no big changes?

I didn't think it's rare that a company refuses to do any work on devices they no longer support. Their employees will no longer be trained to do this work, hence they'd have a nontrivial chance of causing damages. That's exactly why a right to repair is so important, so that other people can pick up their slack

Back when RAM and HDD were using standard parts, Apple packaged manuals with documentation as to how to proceed to such upgrades.