What are the next gen web technologies coming up?

The web is so fast-moving and iterative there aren't really 'generations'. I'd say the biggest growth I've noticed in recent years is CSS. The past ~4 years have seen CSS become a lot more capable, not just for design but also for interactivity, and it doesn't seem to be slowing down.

Single-player internet? At some point, LLMs can probably simulate enough of the entire internet to just fake it on localhost, and any URL you type in will generate a whole website right then and there, customized to your personality, genes, and politics.

The next big web disruption is commercialized, self-hosted, personal servers. Everything is already there except a branding and easy IPv6. Think how disruptive the that will be for businesses based on ad revenue and traffic funnels.

I think the Web (HTML/JS/CSS) is now a much more capable platform but many people didn't notice yet. React fatigue might help it gain traction.