But one thing we don’t have is a true FOSS web, a protocol like HTTP that only allows FOSS websites to be hosted and bars any corporate interest from hosting for profit.

Would something like that be possible?

Possible? Maybe. Meaningful? Not in my opinion.

One principle of free software is that everyone can use it. Also for commercial things. Or for example to control missiles that kill people.

In addition, many companies contribute to the development. Without them, Linux, for example, would not be as developed as it currently is. Whether you like it or not, we need companies. Excluding them would therefore be a mistake.

FOSS is all about giving some things for free, and thats it.

I would disagree with that. Free as in freedom, not as in free beer. The GPL as an example even encourages to charge as much as you want or can for the software.

https://www.gnu.org/philosophy/selling.en.html

https://www.gnu.org/philosophy/free-sw.html.en

There is no such thing as the objectively best solution. Each tool has advantages and disadvantages. And every user has different preferences and requirements.

Personally, I am using Borg for years. And I have had to restore data several times, which has worked every time.

In addition to Borg, you can also look at Borgmatic. This wrapper extends the functionality and makes some things easier.

And if you want to use a graphical user interface, you can have a look at Vorta or Pika.