From the new terms:
When you upload or input information through Firefox, you hereby grant us a nonexclusive, royalty-free, worldwide license to use that information to help you navigate, experience, and interact with online content as you indicate with your use of Firefox.
Honestly you already start at paragraph 1 with a wrong premise and then go down from there. Allow me to point you to the very beginning, to your first emphasis:
Here’s the trick: they are not operating Firefox, we are. It’s a system that runs locally and under our instruction on our devices. When I type something in the URL bar, or when I click Open File, or when I mouse over the screen, Mozilla doesn’t have to do anything: everyhting happens locally. No data should be being transmitted or be processed over their systems: Firefox is not a remote desktop / “live service” application.
…Unless…
And there you have it. That’s why those terms are here.