NiftyFifty, I don't think having a gallery solely for "beginners" would be beneficial to any of the "beginners" in the long run. Galleries for all, already exist across PF.
My understanding of the Exclusive Gallery is that anyone could add their images then approved like any other valid gallery. I believe it is an attempt at improving on PPG right here on PF (see PPG threads here on PF for background).
The Exclusive Gallery is not excluding but inclusive.
So anybody from "beginners" to whatever is deemed "professionals or hobbyists with pro-level skills" can offer their shots to be accepted or declined. Perhaps you may be looking for an explanation of why a shot was accepted or declined. And that could be helpful but that is a different issue. But I believe that just looking at others’ accepted work and responses to it, is a learning process.
If for some reason any of the "beginners" feels overwhelmed by the work posted in the Exclusive Gallery that may be understandable to some degree (I felt a little intimidated early on about posting pictures in general), then there are other venues on this forum to post pictures and receive responses. Many take advantage of this.
Maybe it's something to think about.
As mentioned earlier by others, there are Monthly contests, challenges, themes, the Critique section and others beyond the Gallery, World Pentax Day, and the Exclusive Gallery where members can post their images and receive a response. One may debate the quality of photos or responses but they come from all sorts of photographic backgrounds. And therein lies the beauty.
Fear not in posting in these other sections because the learning will be more genuine and honest than simply posting in a gallery where all are "beginners."
I have not posted to the Exclusive Gallery YET because I don’t feel I am to that level, but have taken advantage of the other image posting sections on PF. The return has been great for my personal photographic growth and so has my learning of what others are doing.
Perhaps that is a path you may want to consider after all.
Good Luck.