Although this largely comes down to opinion, there are some facts invovled. Not to deny the existence of any nuance in the cartoons of the 90s, but there was significantly less than now. The 90s were kind of a pioneering time for cartoons, marketing and branding. New technology on all fronts created a fertile ground upon which to create. These cartoons, all with incredibly rich visual languages, didn’t really rely on the depth of their stories as much as how they looked and how they could be packaged. 

This isn’t a bad tactic either. Kids in the 90s bought a lot of toys, there wasn’t really the internet or variety of games consoles that there are now. So, considering most cartoons were on free television channels, the money came from making kids want to buy them. This isn’t hard - you’ve just got to make them ‘cool’. Make them so cool, in fact, that kids play out their favourite cartoons in drawing books, in their heads, with their friends and with toys. 

Nowhere is this clearer than with the Teenage Mutant Ninja Turtle franchise. The stories were all fairly formulaic, but the characterisation is what drew people in. Everyone had a favourite, everyone had one that they’d choose to be when they were with their mates. Sure, the way they behaved throughout the episodes was also fairly repetitive, but this was the point. They had a personality and their same-ness provided comfort. Cartoons were an immersive, space whose characters became companions.

Popular cartoons now have a different market. Adventure Time, for one, is highly popular - not just with kids, but across all age groups. The humour is deep. There are many layers to interpretation and, in general, the level of writing is incredibly high. People watching it are less inclined to buy toys - that’s just not the done thing anymore, or at least not like it used to be. The audience now is online, resultantly more nuanced, exposed as younger people are to a much wider breadth of both knowledge, but also culture and experience.

In the 90s, you watched what was on TV. Now shows must compete with video games, streaming and on-demand. Cartoons need to have more than ‘cool’ characters to hook people in. The stories, told in an age of far more limited attention spans (both from social media saturation and the freedom of choice granted by the internet), must be far richer and multifaceted. A simple ‘good guy’ versus ‘bad guy’ arc won’t cut it. You’ll rarely, if ever, find a popular cartoon now with those dynamics. 

What you will find though, are cartoons that are lighter on the surface, like Adventure Time, that contain complex themes. This artistic direction very rarely existed in 90s cartoons. It was as simple as the palette and tone reflecting the mood. Dark colouring and foreboding music meant that something more sinister was at play. Light visuals and soft music were always easy going moments. You didn't have to think too hard. Complexity in contemporary cartoons comes from the literacy that younger people now have - their abilities to ‘read between the lines’.

This is a clear positive, that younger people are being treated as more capable. Yet, it’s no coincidence that shows like Adventure Time have found a more mature audience, something that 90s cartoons wouldn’t really have ever had. That being said, people often long for simpler times and the cartoons of their youth will always provide that comfort. It’s not about age, but era. The highly individual character personalities of 90s cartoons definitely stood out.

They were unique, focussing on characters and providing an important building block for their young audience. Life wasn’t about complicated and multi-tiered scenarios - that stuff was for adults. It was about having fun and most importantly, seeing the best parts of different characters and incorporating them into yourself in a formative composite of the unconscious.