For me, the 90s were the golden age of cartoons but maybe because that's when I grew up? I think it's more than that. This was around the time cartoons more commonly started integrating some more adult content. I'm fully aware that The Flintstones was THE first animated series directed towards adults, but at the time, it was still considered a tame show. Then my point leads to The Simpsons which was an IDEAL 90s animated series. The Simpsons catered to adults in a more vigor way, however, children might have a hard time getting into it.
However, this all might've triggered a new wave of cartoon influence that also eventually leaked into the channels directed towards children. Nickelodeon in this case, Cartoon Network... not so much. There's still one element I want to talk about still so I'll come back to this.
THE 90s Nick show according to the general is Ren & Stimpy. Ren & Stimpy combines a retrospective level of animation and physics associated with Looney Toons even and fuses with occasional adult content. I've watched a lot of cartoons back then, including Ren & Stimpy and the subject here; Rocko's Modern Life. Enjoy them both, but at the time I was also oblivious to the adult content while obviously not pushing through the PG line, yet, my attention remains captured because these shows are about appealing to children and adults alike which was an issue finally addressed. Because you have the anthropomorphic characters fashioned through animation/physics of a 40s/50s revival type of style and pairs it with occasional references that the "adults" would understand.
When these shows' respective series have ended, yes I did move on, until around mid 2000s I remember catching a Rocko's Modern Life episode late at night on a Nick channel and it was heart-warming, brought back memories. Nostalgia effect probably, but because I have aged a little more, I now understand more things about these two shows than I previously haven't.
But now the history lesson is out of the way I want to settle the score in which of those two shows I actually like more. Rocko likely derived from Ren & Stimpy which sparked a little accusation of parasitism (I don't care about this. Influence is natural and I do believe in exceeding over your peers). Animation fluency and physics from both shows are good and you'll always get an element of laugh-ability from either. Ren & Stimpy however did last longer.
But now here is why I prefer Rocko's Modern Life. It has all of the contents I've previously described, yet it still manages to be warm and homey where as Ren & Stimpy might get a little carried away. I have a far bigger connection to the characters as well. Rocko himself is a mild-mannered down to Earth wallaby, friendly, not looking for attention, but nevertheless situations that dart at him brings the most out of his character, including timidness, sadness and irritation. Rocko is probably my favorite cartoon character ever created. Heffer the steer is a mooch (in a good way) and sort of like a frat boy buddy to Rocko. Filburt is a finicky and oftentimes bi-polar turtle.
The setting is like everyday life of young adulthood (love, finance, community, etc) with realistic elements and some fantasy ones mixed together and it oftentimes parodies/satires some of the objects on the show to real life.
All together, there are so many elements in this show, elements that would even seem to contrast with each other... but it doesn't. Childish, adult, warm, punishing, friendly, aggressive. All of it is there. I just wish the show didn't stop at 4 seasons, because I can't get enough of it.
I'm not discrediting Ren & Stimpy by any means. It's still my second favorite animated series ever.