Being an Oregon camper I found all parks maxed out. State parks are always full during summer so no change there. It was the Fs types that were packed. It was trending that way for the last 3 years. 10 years ago you could arrive on a Friday night around 6:00 pm and get a spot. In the last 3-4 years the show up times decreased and most of the FS campgrounds we frequent started filling up on Thursday afternoon.
Last year was a mess and even some of the RV parks we frequent were packed all summer even during the week.
With record sales predicted again for 2021 and many newbies still enjoying the RV lifestyle I don't see much changing here.
YMMV in other states.