Because automating deleting them in a robust way is a hard problem (roughly the same as the one image search engines have to solve, and maybe legally problematic in the case of photos of minors, though I doubt they'd be prosecuted for storing them for the purpose of keeping people from reposting them), and doing it by hand isn't feasible with their small staff if enough people insist on reposting them? Cribbing from John Gilmore is disingenuous because Reddit is a single site owned by a single company, but I can definitely see why they want to be as hands-off as they can.
I could write a book on why it's hard for them to do the right thing. You're right - They've got a tiny staff, they have no robust tools. But when SA decided to make an issue out of /r/creepshots, it took the admins about two hours to make a complete about-face even though they had absolutely no ability to do the policing they said they'd do. So they'll pay lip service to doing the right thing when there's a gun to their head. But lip service to doing the right thing if it's just the right thing? Yeah, no time for that.
And when they banned /r/creepshots the creepers said "I HATE YOU INTERNET DAD" and moved to /r/candidfashionpolice, accomplishing exactly nothing other than making the news coverage stop. Banning borderline illegal subreddits before they started attracting bad press would be a nice symbolic gesture, and maybe save them some scrambling later, but it's at least not clear that it would accomplish anything more than that.
Right - it was seen as an arbitrary action with no real power behind it. I made that point then and I made it loudly. The problem is it's a social network, which means there has to be some social attempt to steer it towards the behavior you want. Saydrah was doxxed in '08. Sometime in 2013 they finally decided that doxxing wasn't okay, and by mid 2014 it was something that everybody jumped on as "not done" (while there were throwaways and renegades that perpetrated and perpetuated the problem). Brigading has been a problem from the very beginning, but Reddit started to get serious about it last year with .np links. Now brigading has dropped almost to nothing. So what we're left with is this: A website that has known what its problems are since '07 or before but has made no attempt whatsoever to steer the conversation in the direction of decency. Reddit could come out in favor of privacy and respect towards women and get things moving in that direction, but they don't. Their justification for taking down the fappening posts had nothing to do about violating the privacy of public individuals and everything to do with their pre-existing "bust Al Capone for tax evasion" policies. You're essentially making my point: they act, but their acts are too little, too late and in the wrong direction. You're not making my bigger point, though: as soon as they actually do something, it tends to be effective. I'm deeply dispirited by Reddit. There's an institutional refusal to do the right thing until it's far, far too late and I believe that it's bad for the Internet in general. We're raising a generation of kids that can't communicate, believe anonymous retaliation is the best balm for wounded pride and have no problem upskirting someone so long as they're famous. It's straight up bad for humanity.
I thought we were talking about the admins taking up the role of sitewide moderators, so I argued that that would be impractical to do right and that making token efforts doesn't accomplish anything. Exerting social pressure on users to not invade others' privacy by appealing to values already commonly held on the Internet has worked in the past. Do you think the reddit admins' opinions carry enough weight that they can say "we all value privacy here. Please be consistent and extend your respect for privacy to celebrities/women in general" and have it work? It hasn't when other people have said it.
Don't get me wrong - the mechanical reasons you list for the difficulties they face are en pointe. I dispute none of them. And I don't think that "hey guise be nice" is likely to accomplish much. There needs to be a concerted effort from the top down to turn Reddit back into a community - a large one, that respects a great diversity of opinions and interests - but with a set of "core values" that they can defend. In terms of corporate hucksterism, they need "guiding principles." They used to have them - Alexis and Steve salted Reddit heavily with the articles they wanted, created hundreds of shill accounts and sock puppeted their way to a community they wanted (the early and heavy love affair for Ron Paul explained in a nutshell). But ever since, the "guiding principles" or "core values" of Reddit have been "traffic at any cost." 4chan, at its mightiest, had more traffic than Reddit. And it was still run at a loss out of Moot's basement. Traffic only goes so far. At some point you need to point to the kind of traffic you've got. I stopped having that conversation back in '09 - there were plenty of people who were interested in Reddit's numbers until they saw what was driving them (80% porn search). They could do it if they wanted to. But they just don't want to. And it makes me sad.
I started using reddit when it was still written in lisp, I think because of a comp.lang.lisp post about it. I remember those days too, though I was never really part of the community there. The posts they were making were mostly stuff that were circulating in techie circles, or from sites that were popular in them, and the "core values" were those that were common among hackers before the word got appropriated to mean "startup kid". Not coincidentally, most of their early users were techies too. They didn't have to create a community, they imported one that already existed and which they were already a part of. Alexis and Steve's sockpuppeting just made it an attractive place to migrate to at a time when the old watering holes were in decline.