At least for me personally it's a matter of discoverability.
Reblogging is quite commonplace (arguably even engrained) on sites like twitter and tumblr and can give you a huge boost. Non-creators can play a big part in the ecosystem by becoming curators. Someone's gotta search through the trash after all.
dA has journals, groups and Daily Deviations, but none of them really work I think.
Journals are rarely used for curation because non-artists on dA are expected to lurk, due to the site's focus on artists and original content. They're usually just RSS feeds for commission or livestream announcements.
Groups are flooded with so much content that most admins cave and auto-accept (=useless for curation), or put up so many rules that the group doesn't seem fun to join for lurkers. And even those more strictly curated groups usually don't give much kickback. Submitting to groups kinda feels like tagging - you're tagging your upload with "Sailor Moon", chances are you'll want to submit it to the big Sailor Moon groups, too.
Daily Deviations (staff picks) can differ wildly in quality and have been obfuscated by the redesign. The best boost out of all I've listed tho.
Honorable mention to the useless "More from" system. "More from this artist" just picks a random deviation from the gallery and posts it and the 8 deviations that were submitted right after it. So if the system randomly hits old/terrible/irrelevant art, tough luck. "More from deviantart" always seems to pick the least relevant tags from your submission. You tag something with "logo, skull, skeleton, undead, skelly", and the recommendation will show random logos.
That's my personal experience and speculation anyway.
I think there's a lot that dA could glean from other sites (not just discoverability options), but at this point it feels like an inflexible giant to me. I'd sooner expect newgrounds to go through a renaissance.