Something that's frustrating to me wrt Safari is my, admittedly edge case, in which the company I work for won't allow using personal Apple IDs on company supplied macs. Apple only allow Safari sync to work between computers with the same Apple ID, which I sort of get, but still that makes it useless to me.

This same-Apple-ID restriction causes other issues too, like not being able to use my iPhone as a webcam on my work mac even though I can use my AirPods on that same mac because reasons.

Luckily for me, I'm super happy with Firefox.