No. What's mandated by law is to not track users for reasons not core to delivering your service OR disclose that you are doing so.

The opposite: it's mandated that you not do data collection and tracking for reasons except those essential for the company to provide the product or service, absent informed consent. (And this is purely for tracking: cookies used for maintaining preferences or other state are fine.)

The banners are a fig leaf for behavior that violates the spirit of the GDPR, creating an aggravation where the simplest way to dismiss them is by agreeing.

Any site that doesn't offer a button to reject the tracking (with no more stops than angreeing) and still function as expected without the tracking, is in violation of the law.

Only if you use cookies; I think not everyone will need to use cookies. I think if you use cookies to login, then only the login form should hopefully need to mention the cookies. (However, there are better ways to do user authentication, such as basic HTTP auth or X.509 auth; neither of which requires cookies.)

I read their comments as knowing that.

Imagine a world where you don't need to click on anything because cookies are no longer being used for large scale tracking.

I find it interesting how even if I accept cookies many sites still continue to ask

you don't have to ask for cookies if you don't use them