The SCCA racer numbers have not increased. The racers that we have, have moved to the Miata. Better car with better racing. The 1.6 cars can be bought for 6K and raced against similar cars. When you get done with it, it is still worth 6K. They eat very little at midpack levels.
The It class offer a lot fewer cars in class and more maintenance, while just a bigger hole to poor cash.
Any younger guys that rent or build cars are going SM.
The market has moved away from the old IT cars. ITB and C cars can be bought for sub 2K. Great value, fair racing. Many older cheaper IT cars have moved to prod or Chumpemons.