I recently downgraded one of my macs so i could use some 32 bit audio peripherals. You can’t update safari separately from the os i found out, and most websites now just won’t render with that os and if they do, barely work. I installed firefox and that was fine.

OTH, i use safari on my other mac, it’s fine most of the time, but i also have have chrome installed as some websites are so buggy otherwise, linkedin is a particular culprit, it barely works on chrome too.