You can still get some good pick-up groups, granted every pug I join is made up mostly of eclipse AS people. However the reason that is, is because I like to play with people I know, Hrymf was a lowbie warden when we started running regular pugs, but he proved himself as a capable warden and I am always happy to see him in any pug I run in.
Its all about networking, the same is true irl as well as in game..many people are affraid to ask the high rr/more serious player for a group spot becuase they think they have a chance in hell. But if you keep asking, and keep playing one day you might get a chance to get in to a group and prove yourself and then fall in with the main crowd of FG pug's/guilds.
I play fairly casual these days (3/4 nighst a week) but I still get group offers and I play in a severance group 3 times a week. We are not the gratest guild group ever, but we hold out own against the best any realm has to offer atm (which is not that great imo)
Bottom line is, fitting in with the right players that makes the good rpts and kills the good groups takes time and effort, you cant expect to just fall in with the hardcore players who all know each other, with ease. Just like all things in life, if you want something, you gotta work to earn it.