We can't keep backwards compatibility forever or software is just going to get worse and worse.
In fact, often backwards compatibility is what keeps things from getting worse because the current environment would have never allowed something as good if it wasn't already entrenched. A good example of this is EMail - big tech has no interest in interopability and aside of upcoming laws forcing them there is no way that a federated communication system like EMail would have any chance today.
You can remove "safely" for old enough browsers. They will refuse to connect because of old certificates, or won't be able to understand new ciphers.
It’s so much easier to interface all that hardware just from an intranet website, instead of rolling out your own native code to thousands of different devices with different operating systems. We did that in the past, now they all just run chrome.
go to some website => solve problem => finish
without extra steps. As a user I usually really don't care, I just am not interested in the problem and I am already spending too much time with stuff I am not interested in.
The wheel was almost certainly not invented for the automobile, and yet, your car has four of them.
If you don't like how all the applications are built on the web, by all means, provide a native alternative that's better.
Microsoft under Ballmer would have loved something like that, and spent a lot of money on trying to beat the web.
I really hope we never remove these API surfaces from the web API surface.