That's pretty much what I said in my last line. The problem is, "opening up more" generally tends to mean things like less masking and less social distancing. So to the extent that Rt is pushed down by mitigation measures, Rt gets pushed back up when those mitigation measures end.
The advantage in my mind is you can avoid the most costly mitigation strategies.
Unfortunately, vaccination rates are age dependent so opening schools is a very high risk activity. Children are at low risk for COVID but they would be a major vector for transmission as everyone under 12 is unvaccinated.
