Yes 720 fixed the issue for me today on Roku device and now Paramount+ works fine. I agree that paramount and Roku need to resolve and also provide tech support with a entry in the knowledge base that points directly to this resolution for the problem.
Roku did not point me in the right direction but paramount did along with 10 other things it might be. This one was the only one that made sense so I tried it first and it worked. I did do a Roku restart after the change just in case.