The presence of risk doesn't short-circuit checks and balances. Governments manage risk all the time.
Emergency powers are for emergencies. It is no longer hour four in the incident command tent with a map and radio. It has been, and it may be again. But the steady state "waiting for a vaccine" stage is not that.
The normal mechanisms of government are logistically feasible on the time scale you're talking about, which is years. I hope they will listen to the experts. It worries me deeply that they seem not to be headed that way. But "I disagree with the legislature" is tautologically not a justification for emergency powers in a democracy.
Testing and contact tracing are not novel.
