What you're describing is basically Libra with slightly better entities backing it. Transactions can be reversed by those "trusted entities" with no recourse by you and at no cost to them. At least with PoW and PoS (to an extent), attempting to reverse transactions has a cost.
Speaking of PoS, were the issues with PoS ever solved? Specifically the "nothing at stake" problem. The Wikipedia page[1]'s list of implementations makes it sound like it's not at parity with PoW in terms of security.
What you're describing is basically Libra with slightly better entities backing it. Transactions can be reversed by those "trusted entities" with no recourse by you and at no cost to them. At least with PoW and PoS (to an extent), attempting to reverse transactions has a cost.
Speaking of PoS, were the issues with PoS ever solved? Specifically the "nothing at stake" problem. The Wikipedia page[1]'s list of implementations makes it sound like it's not at parity with PoW in terms of security.
[1] https://en.wikipedia.org/wiki/Proof_of_stake