What would be great is a Homebrew-compatible system that doesn't cut off support for older machines. I have a 3.8 GHz Quad core i5 iMac that still crushes, yet Homebrew has determined that I'm just too old and icky[1] to work with anymore. I had to move over to MacPorts, which is surprisingly nice, but I still miss brew.
Yea, I know. It's open source. They can do what they want. Still sucks.
Run Linux on it. Apple has cut that OS off anyway. Would be safer security wise to have an OS that's updated
Yes MacPorts is the way. I switched after a new MacOS release meant mine was too old - brew update uninstalled a bunch of stuff I had been using then it stopped and let me know.
There's also https://github.com/dortania/OpenCore-Legacy-Patcher for the adventurous.
You could use the OpenCode legacy patcher to upgrade to v15/Sequoia: https://dortania.github.io/OpenCore-Legacy-Patcher/
To be fair, Apple stopped providing security fixes for Mojave ~4+ years ago, and there have been 7 or 8 new os releases since then…
I don’t think it’s reasonable to expect an open source project to support everything