I'm no expert, but wouldn't a startup want a designer who wasn't so picky? Instead wanting a "full stack" designer; who could solve all their visual worries?
Again, I'm no expert and I'm just a technical nerd who "doesn't get" designers. Probably should keep my mouth shut, in retrospect ;)
It's the design equivalent of asking for a developer who is an expert in front-end, back-end, databases, operations, scaling, etc. etc.