Its actually a bit more of a complicated issue than what you’d think. Basically, Japanese pop culture went through a massive shift in the postwar era, especially during and immediately following the American occupation. The Americans had two main goals following the war, to keep Japan in check but also help them grow into a more “modern” (read: western) country and stimulate economic growth. Part of this was done through heavily censoring and Americanizing all the media produced. They forced American values like pda (the first onscreen kiss was like. A HUGE and controversial deal) while at the same time severely restricting things like violence (swords weren’t even allowed to be shown unsheathed). They also wanted to focus on Japan’s rich history of classic heroic and romantic tales. Pretty much, they defanged Japanese media for consumption in the west, because the people back home just fought a war against those guys and don’t want to see anything too scary.
Of course, when the Americans pulled out there was a lot of media that explored the new Japanese identity and criticized America as well as the Japanese government. They explored violence and sex and everything in between, and some really good shit was made. But there was a lot of romanticism, and again things got… kinda dumbed down for the movies. People wanted tales of chivalry and heroics, so they got historical dramas, samurai movies, and yakuza movies. The cultural conception of these historically kinda awful groups were changed, softening things that were actually pretty terrible.
But what about the stuff that was actually making a statement? The stuff that was criticizing America and its handling of the war, or the government or society? It was there. It was doing its thing, making people talk and think. But what about when it came over to the west? We’d spent a solid decade trying to portray the Japanese as this exotic culture, beautiful but dumb and not scary, so that they wouldn’t be completely shunned when trying to integrate back into the world. And suddenly you get all this art with complex ideas and concepts and whoops, we can’t have that its so contrary to everything we’ve been working towards. Besides, what would Americans understand about Japanese politics? Nothing! They don’t care about it! So they cut it. For example: Godzilla. It was originally a pretty scathing criticism of America’s handling of the atomic bomb and everything after, but boy howdy can’t show that in America! So they reduce it to big green monster stomps all over Tokyo, wow what will those wacky Japanese think up next! And what happens? Its hugely successful.
So Japan sees all the woobificaion going on and, can you believe it, its selling! And boy howdy isn’t that a great way to stimulate an economy. So they put a lot of effort into branding themselves as the cutting edge in tech and pop culture, nevermind all the nasty stuff because hey, that’s not good for business. The anime and the pocky and the kimono, THAT’S whats selling so its what’s seen around the world and what Japan becomes known for. And from there its a lot of tell yourself the same lie over and over again and it becomes true, along with the cultural norm of not standing out or pushing the status quo. All of the problems are essentially swept under the rug, and people both in and outside of Japan start to take it to heart. There are absolutely still groups speaking out and artists making AMAZING things like superflat mentioned above (seriously, look into Takashi Murakami, he’s such a cool artist) but very rarely do things like that get noticed on a large enough scale to cause change in something as removed as western nerd culture.
I wanna end this way too long post by mentioning that every. single. one. of my professors, both Japanese and American, has addressed the Japanese dream factory idea. We talk about groups like the Ainu, Zainichi Koreans, Ryuukyuu Islanders, hafu, Burakumin, and so many more, and I know other professors around the country do the same thing because they’re TIRED of all the weebs coming into their classes thinking they’re experts on Japan when they don’t know anything beyond a manufactured image and some vague ideas of bushido or whatever. If you want to learn about Japanese minority groups, look up any of those I mentioned above. Do your research on Japanese conviction rates, which are honestly. Fucking awful. Read some classic Japanese lit, learn about Japan’s nationalism, do SOMETHING other than just consume anime. If you want to know more about the things I talked about, I recommend E. Taylor Atkins A History of Popular Culture in Japan or trying to find articles by Susan Napier, she’s one of the few westerners who studies anime and manga in an academic light.
TL;DR: a good part* of the reason why so many weebs are Like That is because Japan had that image forced upon them, then figured out it sells and decided to brand their country that way, try and educate yourself so you’re not Like That.