I've stayed at WP for many years, but will now avoid holiday weekends. Made the mistake of staying there over the 4th of July. Very crowded with some sites with 4 tents on them. Woken up at 2 AM by a guy and woman screaming at each other in some kind of domestic dispute. Shower building was filthy with overflowing toilets. Not sure who takes care of these things, but they really dropped the ball.
Regular weekends have been fine but can be noisy during high season. If you're a light sleeper, be aware that BNSF trains blow their horns for a nearby road crossing and possibly the bridge on the north side of the park.
The cabins are nice and the lodge restaurant serves decent food at reasonable prices.