I started buying Macs with more memory, no regrets. An M4 Max with 64GB (in a laptop, no less!) runs most small models comfortably (but get 96GB or more if you really intend to use 70B models regularly). And when I'm not running LLMs, the memory is useful for other stuff.
Not the person you replied to but auto discard only helps so much. Even with it on I often use 80-90% memory (albeit on Windows, not sure if macOS is any different in this regard).
Firefox here too, no such problems. I do however run Google services in a separate browser (Brave or Chromium) because most of them hog the Firefox browser. For example running earth.google.com on FF is... a very special experience. :-/
