There are several points I'd like to hit re: this topic.
A) Japanese animation is a hell of a lot older then 60s or 70s. It's progression being a lot like american animation (late 1910s/early 1920s). So... I'm not really sure what your first point was in regards to that, but yes, anime is old. But american animation is older (look up J. Stuart Blackton). I mean, we can go further and break it down to zoetropes and phenakistoscopes but this isn't history of animation and at that point we'd just be arguing semantics.
B) Anime is not geared solely to teenagers. Like western cartoons it runs the gamut from kids shows to... well, hentai. There are art house flicks, and there are big explodey blockbuster series and cutesy children shows. I was about to name western animated movies/series but I got stuck trying to figure out where I would put Heavy Metal (art house? no, too masturbatory. porn? hardly.) in relation to Triplets of Belleville (yeah, yeah, it's french)
2B) This brings me to the point that the idea of westerners solely finding animation "childish" is in itself a close minded concept. I would argue that animation is certainly ingrained into current western society as being acceptable to watch past the age of 13, Simpsons, south park, family guy, futurama, king of the hill, boondocks, etc. being the topic of many an office break room conversation. I mean look at Pixar. Just because it says family friendly doesn't mean it's just for kids (it just means they can sell more tickets), in fact, I'm often amazed at how much of the jokes are aimed at adults. Also, Tom and Jerry is violent as fuck.
To sum up, I don't think animation is as looked down upon in the west as you may believe especially within the past 20 years.
Now, that brings me to the next point I'd like to talk about dealing specifically with Japanese Animation.
There is resistance towards anime for several reasons including:
- A majority of anime... is TERRIBLE. Like, seriously, and I love anime. But the tropes, oh my god the rehashed tropes!
- Cultural differences can sometimes be night and day. You really think you can drop a show like Sayonara Zetsubou Sensei (or anything from SHAFT for that matter) into primetime television and it would work? Hardly, that entire show is a japanese cultural joke. It works for anime fans because they already have that frame of reference to work off of.
And truth be told, a lot of these cultural differences are incredibly frustrating to an audience unused to it. Look at Japan's take on romance, sex, drinking/drugs, etc. (when it isn't hentai... and sometimes even still). I'm going to quote my friend because he makes an excellent point on the current problem with Japanese culture:
Because in a world where globalization is happening and cultural borders are falling due to the influence of the whole world being connected, Japan is still trying to be "Japanese" without recognizing that their youth is changing due to not being an isolationist country anymore
And that culture can still be retained over time, but it needs to change and evolve and become the new culture or else its going to fail
Having said all that, the style of japanese anime IS TOTALLY TAKING OVER THE US
I'm serious, look at a majority of the western born animated series (aimed at kids) coming out today. Teen Titans, Ben 10 (which is HUGE in asia... I found much irony in that), FREAKING AVATAR and a slew of others. Tell me that isn't at all influenced by anime. No no, I think what we're seeing now is a huge overlap in style and it's kind of sad in a way, because now animation is becoming incredibly homogenized (though inevitable, as with all things, thanks to globalization).
Ok, I wrote too much, and it's a bit disjointed but I didn't want to write more. Sorry for being so... argumentative. *phew*