I honestly think a lot of it comes down the ammo shortage as rtschl and others have mentioned. When it costs that much to go shoot, many just take a break for a while (I almost felt dirty going through 9mm last week with a new toy

).
My guess is we will see an upsurge in activity (and hopefully members) on or around September 1 with the Constitutional carry going into affect as there will be some people looking for a place to help them figure out how to navigate the new laws. As many others have stated, this is the first site I point people to when I talk about shooting or concealed carry because it is such an archive of good knowledge (and the best free gun help advice bar none).