I'm aware you can opt-out of this in other browsers, but the default is to emit user input to Google, without the user being made aware. In Brave, if you wish to send your keystrokes to a third-party, you must opt-in. That's the key difference here.

Thanks for confirming that Brave has keyloggers (by your own definition) and has no difference from other browsers.

No difference? There's a huge difference between transmitting user input with and without explicit consent. Do you think there is no difference between me taking your car without asking, and you lending me your car?