Ultimately, the problem is much bigger than /etc/machine-id since there are dozens of hardware IDs on any PC that can be used by malicious telemetry to silently to uniquely identify and track you, and the only solution to this problem currently is to make sure you really trust any software you use.
Systemd, in particular, acts a lot like malware for Linux because if you try to reset your machine-id a long list of stuff that breaks in in it. You could make a cron script to reset /etc/machine-id every day, but machine-id is so deep in the stack that you’d also have to reboot to ensure it’s updated.
I stated two things, that machine-id is used and that adoption is high. You’re ignoring the latter. Might be correlation or causation, but definitely not tautology.
This is a gross misrepresentation of my words. I’m not saying it’s necessary, I’m saying it contributed to the success of some of the most private distros that exist today. In other words a net positive. You provided zero evidence that it was a net negative, and demonstrated ignorance about the complexity of engineering.
Either you keep misunderstanding my argument, or deliberately misrepresenting it to avoid admitting its merits. It’s becoming clear which is true.