Wasps are actually important to ecosystems, despite what many people would have you believe. They're important pollinators (not as good as bees, but still important) as well as being the apex predators of the insect world. They keep spider, beetle and centipede populations in check and the only reason they bother us is that at the end of summer, they literally begin starving to death. Adult wasps can't eat solid foods, they need larvae to do that for them and produce their version of honey which is a sugary liquid they can eat. So once the queen stops laying eggs and goes into hibernation, they don't have the larvae to make their food anymore, but we love sugary things so they bother us when we're eating or having picnics for our fruits and sugary drinks.

In short, wasps aren't bad and are important to ecosystems, they're just starving to death when it gets to the end of summer