Depends on definitions. I could forsee a lot of otherwise centralized platforms adopting decentralized protocols - along the lines of Threads adopting ActivityPub or banks utilizing stable coins.

I doubt most people will ever be managing keys, just like most people will probably never be changing their car's oil. But they might very well be using a service that uses decentralized systems under the hood, and would work with people who are using the systems directly.

The only way I'd expect to see a huge bump in people doing this directly is if countries end up completely debasing their currencies or if they completely lock down social media - then there might be a big bump in users in those particular nations.

My 2c anyway