Again, as has been said frequently here: you don't have to have an ID card to travel on commercial aircraft. If you don't have an acceptable ID card, you have to reveal a great deal of your personal information to a TSO, who then verifies that information against various databases, as a means of establishing your identity. This is true now, and has been true for some time.

So, in the unlikely event that GA decided to get out of the identity card business, it wouldn't automatically deny GA residents the opportunity to fly. There are always alternatives: get an alternative ID like a passport, or submit to the identity verification interview. They're both "costly", but in different ways.