It's more the latter - as far as I am aware, eliminating specifically the human pathogenic mosquitoes will still leave plenty of other mosquito-adjacent species that can't or don't bite humans, or can't / don't transmit the critical diseases.

I think for the releasing-sterile-mosquitoes angle, it's actually more interesting to me to use some kind of molecular clock, I think I read about a genetic modification that resulted in a generation or two of fertile males, but then the Nth generation is sterile as a result of the molecular clock unwinding.

Less mosquitoes, more bees please :)