1) Isn't that tick rate not frame rate? Is there really a tangible benefit to rendering 140fps over 60? I always read that beyond 60 had huge diminishing returns and was hard to detect as a human.
2) Is it really necessary for anything beyond a competitive shooter with bullets flying around? Outside of the bullets, fighting games are as or more precise than the average shooter and 60fps continues to be the standard there and I don't think >60 tick rate would bring any big value to a fighting game. A 60fps game with no buffer can already yield situations that are close to or beyond human execution (see: Melee)
I'm not actually sure requestAnimationFrame() in a browser ever gets you >60 fps. At that point, honestly, you'd probably need an independent render thread (doing some degree of interpolation) and stick to a 60fps logic tick. Which you can theoretically do in JS using web workers, though I know message-passing incurs some serious overhead in that case.
Depends on the browser, but at least in Firefox and Chrome it should match actual refresh rate if the graphics stack plays properly. (i.e. I don't know if it does if GPU acceleration doesn't fully work)
requestAnimationFrame absolutely supports higher than 60 FPS. You can also do all rendering off the main thread with OffscreenCanvas, though you can certainly hit 144 Hz or higher without doing that.
And the new Edge? Of browsers from major vendors at least, I thought Edge was worth mentioning since it recently overtook Firefox in desktop market share.
You don't have a lot of ms