The price of a Safari user in the ad market is going down, and it’s exactly what should be happening. I’m very happy with Apple.
https://9to5mac.com/2019/12/09/apple-safari-privacy-feature-...
You can implement these APIs while at the same time requiring explicit permission from the user before a web application can use them. This preserves privacy while also giving users the option to have much more powerful web applications.
Apple doesn't want to implement these APIs because currently if you want access to these things on iOS, you need to go through their walled garden App Store, where they get a big chunk of any revenue you might make on such a service and can nerf competitors and all the other anti-competitive stuff they're doing.
Why not? It makes complete sense for something like a website that backs up the photos stored on your camera. What's even the counter argument, that if people want to back up their data they should have to pay Apple?
If you've granted a website access to a restricted API, the browser can just paint a flashing red border around the website or whatever, similar to how people configure their terminals when they're SSH'd into prod.