Changing browser config doesn't change anything if the browser want telemetry data but if the browser doesn't respect user settings in UI, it's not very trustworthy. Normal telemetry isn't also bad.
Edge even respect configured Windows privacy settings and "copy" these to browser settings which doesn't any other browser provide.
Yes, but I still can tweak what I want and don't want to share. Developers should let users decide what's "normal telemetry" and what isn't.
Cookie banner are mostly needed as these (if implemented correctly) are Opt-In's or (if wrong implemented) Opt-Out's. Both are need user confirmation and get saved in Cookies so you only get a problem with such if you clean often Cookies which just doesn't make sense. (blocking 3th party Cookies is still recommend!)
Newsletter aren't a problem. Just don't register your mail if you don't want it. Or use random/ fake Email accounts for that.
I never see any floating video annoyances. Examples?
Anti-Adblock popups are gone if you doesn't block Ads
Sites are need money or your data. If you doesn't allow any, they of course display such and personally i find that legit.
Websites can also determine which stuff get blocked
It doesn't matter whether they're needed or whether or not they'll go away if one responds. The point is that they're still annoyances.
For floating videos, there are many examples in sites that usually feature the news. They look like this:
Floating videos allow you to keep the video always visible as the viewer scrolls down the page. When viewers scroll, the video gallery will minimize and float to a corner of the website so they can continue browsing content and watching the video.