How come I don't see any switches or sit-outs at the state and national level at all?

How come they aren't used?

At the higher levels, many wrestlers are more confident on their feet than they are on the bottom. They would would rather stand up and go for a takedown than work for a reversal. This may be because many of the better wrestlers do a lot of freestyle in the off season, where wrestling from neutral is emphasized and there is much less scoring from the bottom. I think a well executed switch (especially an inside switch ) is hard to beat.