I actually see it more likely the opposite - a subset of humans will retreat into a (vastly smaller) human-first world, and AI will be of a separate world concerned with material/scientific/research concerns and appeases the masses who are still around.
We can already see this today in the form of upper class parents (like myself) who vastly restrict their kids screen time and ban social media. We may see AI-free societies that form, but supported by AI. The jobs and roles people play within that society may deal with services that really need to be done by a human, being a buffer from AI to the rest of this society, or just straight up fake.
I personally think this is close to a doomsday scenario - but it doesn't end with a big bang, but more of slow quiet death.
The subset of people who will want to merge will be people who will not be content with having no control over their future. No ability to create new inventions, new discoveries, new ways of working. They will not be content with just having everything provided to them, playing the social games that will remain and think their environment is a prison.