I regularly have recruiters coming to me with jobs in the Bay Area. I tell them that my salary requirement is double for up there versus Los Angeles. A few of the big players will always be able to afford that, but I see smaller tech companies and startups moving away due to cost.
I've seen plenty of "coders" with 15+ years experience maintaining and changing other peoples code that couldn't write code from scratch to save their lives. You see it mostly from people who've spent a lot of time someplace huge and old and corporate.
I applied for an analytics position that unexpectedly had me take a Python coding test like this (I know a bit of PHP and Java but no Python) and I was able to google everything I needed to pass the test in the time limit. Apparently I got one of the higher scores too. Got the job. It has not required me to write a single line of Python, lol.
Googling stuff to copy is one of the most important skills for programmers. I was appalled when a middle aged senior programmer at my first internship told me this, thinking he was lazy and unethical... (people are paying you after all!)... how naive I was!
I see no way of controlling privacy in a decentralized system. It'd be like trying to delete all the emails you've sent to other people or stop someone from forwarding an email. Once you put the data out there in a decentralized system, it's out there permanently. Centralization allows for some control.
This is a big problem I think as well. Do we really want a social network where nothing can be deleted? I have used a few and it definitely makes me think before posting.
