Homebrew's insistence on leaving OSes behind that they deem to be "too old" is becoming a problem as the years click by. One of the reasons to use third party software and a third party package manager is to avoid Apple's own insistence on abandoning old OSes. Homebrew following their example is very disappointing.
EDIT: From the linked issue:
"Intel support is coming to an end from both Apple and Homebrew."
Deeply, deeply disappointing. I know Open Source doesn't owe us anything, but this seems like a terrible turn for what was once great software.