The virus has a couple strikes against it: today's response vs 1918, mutation rate, warmth.
We will actually know in a few months at most about those factors and won't need to wait 2-3 years.
But we certainly don’t know now.
Any of it.
Including the warmth.
We don’t live in unairconditioned buildings any longer.
We shop in them.
We don’t work in them.
We’ll see if the temp has anything to do with this virus.
I suspect it’s more a question of circulating levels of D3 that shut the flu down in the summer. There are myriad papers linking D3 levels to flu susceptibility.