Meanwhile, mosquitoes... pollinating, cleaning waterways as nymphs, females just needing the slightest amount of blood to lay a couple hundred eggs. Forgotten, maligned, made the focus of actual efforts to purposefully cause species extinction. ._.
Mosquitoes don't directly cause death, though.
They are susceptible to diseases. They pass those diseases on. Those diseases cause death.
Bees cause more direct deaths due to anaphylactic shock from allergies to apitoxin.
Not all mosquitoes bite humans. So, you could eradicate the biting variety, and a non-biting variety would step in to fill that ecological niche. I don't see a downside.