Gmail uses Microsoft's ActiveSync and they dropped it years ago because they don't want to pay licensing to Microsoft for the billions of free gmail accounts. ActiveSync is registered to a device which is why some older devices continued to work when they changed over years ago.
However you can purchase a commercial Gmail account and get ActiveSync.
Been using Brave for a week or so. So far I don't like it. Has problem not scrolling to top of newly loaded page and I have to press top, especially in MR site. Safari doesn't do that.
Also trying DDG browser and that seems better. May delete Brave.