I could see them not letting you directly search anymore, only through the LLM bot. Because that’s been how things have been going anyway, Google seems to fully ignore literal searches with quote marks now, presumably because it doesn’t fit their vision of using natural (imprecise) language. So why not make the LLM write the search query for you in a completely opaque way?
No, it’s not that far along. A lot works, but if there’s invasive DRM or anticheat then it probably won’t. If you have specific games you want to play in mind check out https://www.protondb.com/
If you’re curious you can just create a live USB stick to test drive it. Won’t work well for gaming though.