Funnily enough, most designers actually argue the opposite, "flat design" actually makes it harder to get things looking polished because doesn't have as many v

Funnily enough, most designers actually argue the opposite, "flat design" actually makes it harder to get things looking polished because doesn't have as many visual flourishes, so that solid typography, color choice and hierarchy are all extremely important. "Flat design" actually goes to hell pretty quickly. The real lesson is: "flat design" doesn't affect your ability to design things at all, it's all in your head.