

Who says CachyOS is mostly for newer machines?? I don’t know why anyone would make such a claim. At least on their website, no such claim can be found. The official system requirements are listed at https://wiki.cachyos.org/installation/installation_prepare/ , you can switch between minimum and recommended set.
I was on Manjaro before too and can recommend the switch to EndeavourOS too.
















Well, no need to websearch. Just go to the website and look for any official links, such as the wiki. As for the optimized packages, I found this on their website:
So the listed CPUs in the requirements list should take advantage of this I guess. And my assumption is, that these CPUs are required to run the packages at all. Maybe that’s where the “newer machines” is meant with.