It will change things too, not for reddit, but for competitors (like kbin).
A tiny site can only grow so fast, at some point things start breaking (both technically and as a community) and users stop joining, but as sites grow bigger they also gain the ability to grow faster.
The protest means that every possible alternative to reddit has been growing as fast as it can reasonably support. That’s probably not fast enough to hurt reddit this time, but next time it might be.
Republicans have traditionally been the party of “regulation doesn’t work, elect me and I can prove it to you”.
Maybe Musk is just taking the logical counter-part to this “regulation doesn’t work, put me in charge of a heavily regulated company and I can prove it to you”.