This isn’t the search bar though, it’s the “run” window (Win+R), which has no search functionality and is more-or-less equivalent to typing a command in Command Prompt.
I'm actually fairly certain that the Twitter post is referring to the start menu search. I see exactly 0 network requests when typing into the run box.
OP has posted an update... It was actually the start menu search instead of the run dialog...
It has search functionality. I slightly mistyped something the other day and was mystified to see the correct answer in a mini browser window while Windows itself was failing to match it up with the software I had installed and run every day. You can also just start typing search queries and it will try to launch MS Edge as soon as you hit enter.
> Windows cannot find 'foobar'. Make sure you typed the name correctly, and then try again.
Maybe you're not using the latest version. I get a mini browser window inviting me to try www.foobar2000.org. Windows 10, 21H1.