I've been here well to many years, I don't think the quality is what it was 5 or 8 years ago or even back in Air Warrior days, now a few reasons for this.
The economy has really hurt many, I believe quite a few of the quality sticks probably retired or gotten bored with the game.
Thus being said - I don't agree the Quality has changed all to much over the years, I believe its just lack of training and lack of learning that does it.
5 Years ago we had NOE's but not every single mission flown from one country were NOE's, you'd get one or two here and there with a single Squad running them or a pair of squads.
Problem is less then 20% have always been Experts in the cartoon world, 20% or more have been bran new to the game and everyone else is stuck in the middle, whether its lack of interest to learn ACM, or someone who just enjoys flying with his squad and having some time to blow off steam.
Either way I don't think the Quality went down the drain as much in the last few years as the Strategy involved, which really has gone down hill.
When 60 players mass for an NOE, some call this "a mission" others call it a horde, I haven't seen this 5 years ago unless it was squad night for a large squad with 3-4 sub squads, even then there wasn't 40-60 players it was more like 20 was a horde.
Squads arn't training new pilots also, not as effectively as it was 5 years ago, the learning Curve hasn't changed and some either accept the challange or don't.