It does kill/severely impact a lot of adults with whom kids interact, however. My decision to keep my child at home even if schools reopen is based as much on the risk to other members of our family as it is on the risk to her.
And even if it doesn’t kill them, we don’t yet know what long term effects the virus may have on children who contract it.
We will never know that. 10 years from now, people could still be saying "there might be some terrible thing lurking that just hasn't shown up yet!" We're well over a year out from when some of the first infected children recovered, it's time to start ratcheting some of our ideas of this unknown risk down. Also, we have no better idea what long term effects the vaccines may have, but everyone is champing at the bit to assume that risk.
The harms of social isolation and screen learning, on the other hand, are well understood and being inflicted on great masses of children, far more than will ever have a serious symptomatic case of Covid.
I don't think this is true. I don't think we know how this generation will be affected by Zoom 8-4 every day.