With the new Area 51 Discussion Zone, users have their first opportunity to organize and start cleaning up Area 51. There's certainly no shortage of proposals that need to be closed and combined.
But the role of the discussion forums (or even Area 51, in general) is not to have a handful of Meta Area 51 users police the place and pass judgment on every proposal. Discussions are meant for stake holders to have a forum to communicate important issues about their proposals.
When I was sole proprietor of Area 51, my philosophy was to NOT close down people's (poor) ideas. If there's no "market" for a Q&A idea, nobody would support it. I preferred to let that lack of support be the primary means of culling unpopular ideas.
Having said that, I'm hesitant to say what they are doing is wrong or unwelcomed. Most of the proposals closed probably should have been closed. It's mostly low-hanging fruit activities and, to date, the ends have justified the means.
Truth be told, I'd rather see people spending more of their time fixing up the proposals on the commitment end of the process. That's where it counts. The rest is largely inconsequential.
There is still a strong editorial layer in Area 51. We're still getting used to the new discussion process. If I see the process being abused and legitimate proposals closed for the wrong reasons, I have no qualms about stepping in an saying, "If you don't like it, don't support it."