Regarding encryption, I think we'll find a new way to handle that. If quantum computing has to be used, it may be possible to offload the work to a server somehow and temporarily use classical encryption. I'm not completely sure how it would work, though.
A lot of gloom and doom, certainly, but it's justified. AI generated content will probably be easier to identify as people get better at recognizing its telltale characteristics, even if it improves dramatically in quality. I definitely think commercial artists are eventually going to be replaced at the rate the tech is improving. Writers are already on the chopping block.
I don't know; maybe this is the beginning of a transition back to a more offline life for the average person...? "Computers take over the Internet" sounds like a funny headline...