Similar thing happened with the internet when a lot of bedroom servers disappeared. A very similar thing also happened to radio some many years before. If anything, this could be a sign of maturity.
What happened to radio was due to limited spectrum availability and laws prohibiting its use. This can't really be compared to the others.
Bedroom servers still exist, and are probably more popular than before. It just appears there's not so many because they've been largely eclipsed by big players and the ability to just spin up new instances on demand.
Having a bunch of people making millions by racing to compute SHA256 collisions is very much extraordinary IMO. Drawing parallels with the server and radio markets is not very convincing.
Furthermore the way mining happens is pretty irrelevant to Bitcoin adoption and maturity at this point. Having a million miners or only 10 doesn't really change much in terms of usability or price volatility.
The bedroom servers have disappeared in favor of cloud computing like AWS. I'm not sure I'd consider AWS being a major single point of failure a good thing. Not to mention, isn't one of the big selling points of blockchain its distributed nature?
