How many of these features that chrome offers have been fully flushed out and in a true working stable state? Google Chrome has a habit of pushing features out before they're really ready and Safari is usually on par with Firefox for features from what I have seen.
I’ll ask the dual question: how many of the mobile safari checkmarks are fully fleshed out? Media Session has a check, but I have absolutely fought obvious Media Session implementation bugs in my own PWAs when designing for mobile safari
It's not a question of readiness or capability. It's an MBA with a spreadsheet explaining to a room full of people how much money Apple will lose if they allow X feature to work in Safari. This is user-negative behavior from a company that has so much money the best thing they can think of to do with it is to bank it offshore in a tax haven.