You can’t argue “this looks like a wasp so it is a wasp” and then extend from that to “and because of evolutionary history, all these other things that don’t look like wasps are also wasps”

Defining groups of species with a common word is always going to be ambiguous, but you need to stay consistent in what you use to define it. By the same logic you can argue that humans are fish, because whales clearly are fish if you just look at them, and whales and humans are both mammals.