I don't think it matters outside of a snide laugh when weebs use Japanese words. I'm painfully aware most aren't actually interested in learning anything besides what they learn by "osmosis."
But when weebs use a Japanese word, almost no one outside of Japan or folks with Japanese heritage know wtf they're talking about (and even they don't know half the time). That "respect" you're talking about is just forced acknowledgement that the words can't be put in any other context than as a foreign language by the average standard English-only speaker.
A non-black person uses a word taken from AAVE and... most people at least feel like they get it, right or wrong. It's not totally divorced from "standard" English and so the average person feels like they can use it themselves and may not recognize its origins.
I recognize the analogy isn't 1:1, but at the same time English is also filled with a bunch of loanwords from Spanish, French, German, and even Japan. No one is going to balk at "karaoke," for example, even if we butcher the pronunciation. But even then it's understood that it is a Japanese word, and no one has a problem with saying that. Japanese speakers are free to use the word in a way that Black people are not allowed to use much of AAVE without judgement. When it comes from our mouths, it's "ghetto" and "uneducated." It only is given respect when it has been assimilated, and thus destroyed, by white people.
But yes, the use of AAVE might not be as divorced from English as Japanese is linguistically, but that isn't really the realm of where I was trying to rest the analogy. It's the
reaction to when someone is chided for using AAVE in an incorrect or cringy way that is the key difference. The reaction is usually one of defensiveness, because as you said people feel like they can use it for themselves. But the thing is they never asked; it was only assumed they could. And they assume because they don't feel as if Black people can own their own culture the way other groups can, so the outflow of our culture into wider white American culture at large is like a burst pipe.
And sure, the immediate rebuttal to this is the matter of etymological ignorance. People don't
mean to take from Black people; the words just
randomly showed up in their lives one day and they sounded nifty, so they adopted them. It wasn't malicious. But I would then go on to say that naivete is not an excuse, especially when people are likely to be sore learners about the subject. What I mean by a sore learner is that the prospect of learning can absolutely be a veil for subconscious maliciousness. Like, if you were to ask a quantum physicist to explain something to you, it's likely because you understand yours and their relationship to the subject at hand is wildly uneven. You know fuck all about quantum mechanics, and they at least know
something. So you defer to them as an authority. You don't fight their answers and tell them they're wrong, unless your intention the entire time with even asking the question was to ultimately undermine and challenge their expertise.
Black people get fought in matters of Blackness
all the fucking time because non-Black people have never actually had to entertain the idea of Black intellect, expertise, and ownership, so you get this combative-ass shit
all the time whenever these kinds of subjects come up. "You can't redefine the word racism." "Actually, Vikings wore dreadlocks too." "Uhm, that's a double negative." "This is just how culture works." It's an exercise in futility. But the likelihood of a white person trying to actually school a Japanese person on Japanese culture is lower. Like, sure; online where we're all anonymous until we aren't, some cocky weeb might try to spout some nonsense with their whole chest, but they would at least be more willing to shut the fuck up if the person they were talking to revealed their identity as a Japanese person who had lived in Japan for some time. Suddenly, there is some authority regained and the context between the speakers has shifted to that of a novice and master relationship. The Japanese person is now an expert, because Japanese culture is, in itself, a legitimate culture that needs to be experienced to be understood. Black American culture is not held in this regard. It is taken without acknowledgement or respect, and fuck you for trying to reclaim any of it. What are you, a segregationist?
Indeed, it's the idea that Black folks have
any sort of authority over others regarding matters of our culture that pisses people the fuck off. It's why you see so much hemming and hawwing about the n-word that you don't with any other slur. "Why can
they say it when we can't?" The fact that Black people can do something with less impunity than others can is just against the fucking natural order of things. Because we don't own anything. We don't own our land. We don't own our looks. We don't own our music and dances. We don't own our words. We are not to be respected. That is the order of things, based in the literal material reality of how the world even runs in the first place.
Ultimately, white people will never defer to Black people on issues of Black culture in the way that they would defer to Japanese people about Japanese culture. I'm not arguing that they consider Japanese people as equals, or that they genuinely respect Japanese people. I'm arguing that there's definitely a difference in how these things are seen. White people acknowledge that Japan has a culture. White people don't even know the African continent has fucking skyscrapers, much less millenias-old civilizations and cultures that still exist today.