Now that we have plenty of proof of work completed, we don't really need any more. You can bootstrap your new coin by burning Bitcoins as a provable value sink to get it started on the path to POS.
now why would any entities want to deposit usd into a private bank and receive usdt without any yield on their cash? you think you understand tether so well maybe think about it for a few minutes
Like everything in tech, the devil is in the details, algorithm details in this case, so far it seems to be working out just fine.
See criticism here: https://news.ycombinator.com/item?id=25007874
I wish cryptocurrency folks would stop pretending it is about decentralization or distributed systems, and that anything that allows them to bypass financial regulation is good enough.