Yes, that's right.
Per the IRCC policy, those with COPRs issued after March 2020 are not allowed to travel to Canada right now to land due to COVID. As you've said, this is a very well known and public rule.
Agreed the OP cannot travel based on the COPR. The only hope is to try to travel on the work permit while it is still valid.
Yep...bigger problem is if OP loses the WP, than he need to quit his job because he lost his status...Obviously a company is not going to keep him if he does not have a working status under a WP and he's not PR yet because he couldn't do the landing and finalizing the process.