I think there's something I need to clarify regarding my stance (and why it's an "aggressive" one, even though the word feels quite insulting to use in this context) regarding Durin and him not being a child.
As a disabled adult, I display a LOT of "childish" and/or "child-like" features, including but not limited to: not working/unemployed, sleeping with a teddy bear, play with dolls or toys, having a vivid imagination, needing help doing chores and reminders to take care of myself, ectect. I'm also quite short (5'1") and have a very round, child like face.
I am also going to be turning 33 next year.
And the thing is--there are plenty of adults out there who aren't neurodivergent or mentally ill who display childish or child-like behaviors. Some very well adjusted folk still play with toys, some still exercise their childish imagination, some have round baby faces, some get too excited and into a series.
But these people are still adults. Adults are not immune to having childlike wonder and acting "childishly", or having a child-like view of the world. Some remain immature in certain aspects for the rest of their lives.
The reason why this is important here though is because a lot of adults who do display what society thinks of as immature or childish are neurodivergent. There are some who aren't but usually society targets those with neurodivergencies specifically to infantize us, downplay our autonomy, and even take our rights away, all because we aren't seen as "true adults".
Yes, this is a political issue. Sorry, you don't get to run away from that. Ableism isn't something you get to ignore (and even perpetuate) just because you don't like its existence in your fandom space.
Durin has been confirmed as a canon adult by Hoyoverse indirectly by showcasing Durin can be legally served alcohol in an official establishment, which as depicted by Chinese Law, cannot be legal unless he himself was an adult. And no, a Chinese Company cannot depict minors from fantasy versions of other countries drinking alcohol, it does not matter if Mondstadt is Fantasy Germany. Hoyo has to follow their country's laws, not our western ones, even when depicting another country.
That means Durin is, without question, an adult. There is no "but that's just an interpretation" about it. There is no wriggle room. He cannot be under the age of 18 in the eyes of Hoyoverse (his creators) and Chinese Law (his creators' homeland). Insisting he is a child when he literally cannot be one is taking the same rhetoric people use to hurt and abuse neurodivergent people and applying it to an adult character.
Yes, it is ableism. Viewing Durin as a child when he cannot legally by Chinese law be under 18 years old is a form of ableism that the villains of society prey upon to hurt neurodivergent adults. Because you view him as a child for his "immature" or "childish/child-like" behaviors, and if these behaviors are that of only a child, then disabled adults are ~surely~ children themselves who need their autonomy stripped away so they can be "protected". Even neurotypical adults get affected because society demands they lose their autonomy too, their right for play, in favor of being an "adult." Play, curiosity, and other childish behaviors are not exclusive to children, neurodivergencies aside.
It is Ableism because while characters cannot have autonomy, real life adults who act like Durin do have autonomy, and are the ones harmed most by this rhetoric. Your ableism towards Durin is not inconsequential, it doesn't exist only in the bubble of the Genshin Impact fandom. It spreads like a wildfire you cannot see. It reaches other fandoms, outside of fandoms, into the general public of society where it originated from, and then back to the people who want to harm and erase those who don't fit into their perfect cookie cutter box. When you perpetuate that rhetoric, the villains of modern society don't care about the fandom its from. They just care that they have your support, that you're on their side. Maybe not fully, but you've got your toes in the water enough that they can grab you and drag you under with cleverly worded bigotry and even worse rhetoric. And they will, too, because they need the power and are clever enough to see that power lies within numbers. You may think you are immune to propaganda but by dipping your toes into the water you've already shown that you are weak to it so long as it is presented as a societal norm. You may insist you're not even touching the water but you are, you being in denial over your ableism only stands to make you an easy target for propaganda.
This is why I am "aggressive" about the ableism towards Durin. Because fandom bigotry doesn't end at fandom. It exists beyond it, reflecting that of the society we live in today, and perpetuates harmful ideas and rhetorics that only hurt vulnerable people in the end.
I expect that people have and will continue to block me over my pushback, thinking it doesn't matter, thinking that I'm just as aggressive as those who think Durin is a minor, thinking it's all useless fandom wank. I probably will get blocked over this post because it features the discussion of politics in fandom and no one likes that.
But--if I can change one person's mind, correct them from being ableist? If I can get them to challenge their views on what it means to be an adult verses a child? If I can get them to stop spreading the fire and instead spread the correction? Then that's enough for me to keep being "aggressive" about the ableism in this fandom.
So see me as a salt mine, throwing a temper tantrum, being needlessly aggressive, whatever--I don't need people who won't question their ableist beliefs to like me. Hate me if you like. I will still be out here doing the same thing I've always been doing. Whether or not you can find it within yourself to question your ableist beliefs is on you.