In my opinion Crumb was the best practicing artist in any medium of the 60s and 70s. No easel painter or photographer captured the times like he did. Maybe it's worth taking the time to figure out how he did it.
Crumb shocked everybody with his gritty, realistic inner city landscapes (above). Older people didn't seem to mind this ugly and depressing architecture but young people were steeped in bright mod fashions and appealing images in movies and magazines and they hated the old stuff. Nobody knew exactly how much they hated it until Crumb came along and satirized it. 
City streets began to fill with black people wearing outrageous clothes. Nobody would give it a second glance now, but back then white suburbanites were constantly surprised by it. Crumb's the only one who bothered to draw it.
Back then adults didn't watch TV much and they were worried about the effects of TV on kids (above). They had good reason because the modern, clean, exciting world we saw on TV made the ugly, slow-mo real world seem intolerable. Once again, only Crumb bothered to draw that.
Other artists like Peter Max tried to come up with pretty, contemporary styles to represent the modern world. Crumb used a gritty, 1920s style (above). Max misread the generation. He thought theirs was just another fashion change. He failed to get a sense of how deeply the hippies were disgusted by the ugliness around them and how much they wanted warmth and personal connection. Crumb's style was the only one that reflected that. 
There was a new kind of sexuality on the streets (above) but normal artists weren't picking up on it. Glossy magazines had pictures of slick models wearing weird, high-fashion mod clothes but that was the world of glamour...it didn't have much to do with what was on the street. Crumb was the first to suggest that the casual clothes real girls were wearing were sexy.
Crumb resisted getting into a rut. Sometimes he would do fine-artsy type pictures like the one above.
Young white suburbanites had mixed feelings about the newly liberated blacks (above). On the one hand they welcomed the "soul" and style of the blacks, on the other hand they feared the ignorance and coarseness that some blacks brought with them. Young whites of the period were firmly and idealistically committed to civil rights, but they must have found themselves wondering if they had opened Pandora's Box. Only Crumb managed to capture this anxiety.
Are there any parallels to today's situation? What should cartoonists be drawing now? That's a tough question but I'll take a stab at it. My belief is that, unlike the hippies, this generation doesn't want to have its nose rubbed in the ugliness of modern cities. Underground comics that stress sloppy, depressing environments are missing the mark and will fail. The society that's coming will reward artists who can create romantic alternatives to what we have now. That's why the Harry Potter and Lord of the Rings films are so popular. 'Just my opinion. I could be wrong.
The one thing I'm certain of is that you better fill your sketchbooks with drawings of baggy while it's still here. When it's gone it'll be gone forever. Emos are wearing stovepipe jeans and they're the new trendsetters.
