Except for the possibility of unconfirmed transactions if the network is under load right? With both centrally registered clients and counterparts what’s the case for decentralisation here again?
I'm not sure what you mean by centrally registered clients. You can still use bitcoin peer to peer. Also the idea that banning peer to peer bitcoin would be what would make decentralization not worthwhile feels rather circular.
To trade you need to be registered by regulated entity, it’s already a centralised environment. You’re also purchasing shares issued by a centralised issuer, the corporation. Your suggestion that bitcoin offers any solution to settlement (much less a superior solution), just escapes me