Gemini already has better UX than the web and mobile

It's true. Using pretty much any website actually to get something done is now a significant hassle. You have to deal with absurd delays between each mouse click and the browser quiescing to the point where it might be safe to make the next move, and things just judder around uncontrollably and incoherently on-screen, with no indication of what's going on.

Gemini:

is faster than your average website at displaying the same information

is faster than your average website at letting you actually interact with the "content", due to an absense of pop-ups and click-aways and cookie warnings

has a much cleaner visual appearance, minimising distractions and conserving attention and focus

does not have a UI which updates as you attempt to use it: if you start to click on something, it isn't suddenly replaced with a different thing before you can stop yourself

won't have intrusive advertisements

There are probably some "dark UX" patterns for Gemini, or whatever the term is, but they're likely to be much less egregious than the alternatives.

The privacy advantages of Gemini are often touted, but for me the killer app is just the fact that after the page has loaded, there is no longer an obstacle course involved in trying to use it.

Gemini: just less hassle than the Web.