You say this as if it's something that's happening, but it's not. There's a few pockets of self hosted bits here and there, but that's not new. We are not coming back to decentralised systems, and we will -never- go back to that in any significant number.
Most people are not going to give up the cloud to go back to bare metal. Most people are not going to give up their zero-maintenance SaaS app to go self-host something. All of it is just too convenient, and you then also have the inertia working against you; there's a whole generation of developers now that has grown up without ever administering a server. They're not gonna give up their Lambdas and drop down to a lower level, just like I'm not gonna give up my interpreted languages and drop down to C, even though it'd perform a hell of a lot better.
I'm with you - I like self-hosting, and I run everything I can on bare metal, and I hate everything costing money every month. But there's no future in which people decide "oh I'll give up the convenience and the extra money I can make from this" and go back to the old way of doing things.