If you serve web pages, you likely serve many of your users on their Apple devices. And you can’t support features of the web for those users if Apple doesn’t want them to have those features, and prohibits browsers with other engines that do support them on their App Store, and prohibits other sources of web browsers.
That’s called “gatekeeping”.
And no, it isn't. Not supporting certain browser features does not direct traffic or even deny access. So you obviously don't know what gatekeeping is.
No.
And the browser-engine ban is being lifted; something that sounded good at first, until you realize that Chrome is already a cancer on the Web that is only held back to the dominance of Safari on mobile. Cheerleading for a total takeover by Chrome isn't smart if you think it through.