Does anybody actually use anything apart from Safari? I personally see no reason not to as it works fine for me, and I would personally trust Apple more than Google and Microsoft.
Yes? I swear by Microsoft Edge. It is the only browser I use. Even the version of the browser im running via Rosetta 2 works with no issues.
For me, if a browser doesn't have native casting support, it's an automatic no-go. I also love the ability to create as many electron-based webapps as I want. It lets me have my own little webapp for gmail, google calendar, Netflix, etc that keeps my browser less cluttered and lets me focus on one thing at a time with no distractions.
Safari has extremely poor extension support and as other's have mentioned, it works kinda weird on certain websites. If I could cast from Safari and it had the same extension support as chromium browsers, I'd use Safari. Firefox is a very, very unpolished app on the Mac, its interface drives me nuts and it's noticeably slower compared to Safari and Edge. It also has very middle-of-the-road extension support and its mobile app is ass. Edge is so much more efficient than chrome and has slightly better privacy.
My only complaint about Edge on Mac is having to use Microsoft's autoupdater app. But I have to use that app for Microsoft Office 365 anyways so it's not a huge deal.