Steve:   Now this has been a rehash, but lets get to the meat of your question here, which seems to be, boiled down, if you can click a nudity filter, why should it matter that there be no nudity in thumbs.

I can only answer this, based on my personal opinion.  I do not work for renderosity, pay for their server, or anything else, just an artist.  Since my Kevlar's on loan (luck to your son darlin, keep the kevlar as long as you want!), I'll use the easy wash drip dry spatter guard.

Renderosity states, they would like the site to look more professional.  Granted, pleased or not by the thumbnail croppin rule, I have to agree with them.  You see, from the good, bad, and the ugly, this is a business.   There are artists on this site, that would absolutely adore if serious people in the business took a look, and decided to hire, or showcase any one of us, in a magazine, spread, or gallery.   People can lie if they want and say they just "do it for themselves", but I have to think, if people are so adamantly persecuted by showing no boobs in a thumb waving about the elite artist banner, I'd think they'd like to make a few dollars out of what they love to do, if they could.

Let me introduce you to, other than the Naked Vicky in a temple with a sword, to what really is at hand here.......

Its where I'll need the drip dry spatter garment:

"JGPVBMANC"  = Just got Poser, Vicky, Breast Morphs and No Clothes.

If someone working for a high end art magazine was looking for new talent, even if they were looking for graceful nudes, how far do you think they would get in the gallery before they go , "Next?".   Seriously, How many V3 areola's do you need to see in close up, to begin to understand the lack of "something cooking" back there?

Though I do not wholly agree with the thumbnail conundrum, I can see it from a business standpoint.   Do you seriously think an editor from heavy metal magazine, the New Yorker, or the like, would go past even two pages of "whats new" in the galleries before, again, going "Next??".

New users do come here to "look around", and I hate to break it to everyone, first impressions are important!  Would you seriously put in your professional portfolio the boob close up to advertise?  I doubt it.   We as members have had experience with "whats in" the galleries, new users don't know some of the "in your face flying genetalia" that would greet you otherwise, without the thumbnail rule.   I can only imagine what kind of impression that leaves.

On a last note, though that may not totally answer your question, the impression the gallery leaves, does not just reflect on renderosity, but bleeds over into every member who uploads to it.   Every one of us.