Hi! I used to be on here a long time ago but managed to lose access to my account, I have no idea what email I used, so I have a new one.
I am going to attempt to answer this because I identify as a little, because it is just who I am, it is just my personality, mannerisms and interests, but my headspace age level fluctuates I guess so I do regress younger, and I am asexual and diagnosed audhd (autism/adhd), so age regression as a community is the one I frequent because it aligns with the content I want to see and my experiences, as well as the subreddit Never Grew Up, which resonates the most.
I have been trying to word this reply for over an hour now, it is quite hard to put into words.
The overall root problem is sex and sexualisation. As painful as it is for those who do find it sexual, the majority of people will never understand or accept it, or are very unlikely to anyhow. Because for those who haven't felt it or experienced it, it is impossible to understand. It is like avocados, I don't like avocados, I don't understand how it feels to crave an avocado because I never have, and actually thats my experience with sex overall, I lack sexuality, completely. And it is also the same for people who feel the opposite, they'll never understand either, they'll never understand how it feels to lack sexuality, or dislike avocados, and it is frustrating for people to misunderstand your experiences, it makes you feel alone whatever those experiences are. In the case of sexual ABDLs though, it has the extra layer of being a subject that doesn't feel like it should ever be sexualised to most people, their brain automatically connects it with awful things.
There is a vocal minority of ABDLs who insist that it is a kink, it is always sexual, and that you can never regress to the headspace of a child. But that is their own experiences that they are trying to force on others. I think this is what causes the backlash and conflict because people then feel their safe space is threatened, and if they have experienced trauma this is particularly unsettling. I also think some of these ABDLs do it in the first place out of feeling hurt and upset when their own experiences are insulted.
The only real issue age regressors have with ABDL is sexualisation of their own experiences, and the impact the sexualisation has on their own acceptance.
I think agere actually has a much better chance of being fully accepted and normalised by society, it is already met with much more acceptance by people who aren't a part of any of the communities at all when it is explained to them what it is. The key difference to that acceptance? Being told it isn't sexual, it is innocent. And since that is the case with age regressors and the age regression community, they want to protect that acceptance and be able to be themselves I think. To be able to live true to themselves. Honestly, I think this is actually a positive for society overall, I think too many people are stuck denying themselves of things deemed "childish" or "for kids", I think people would be so much happier if they were socially allowed to just play, watch cartoons and like what they like, whether that's dinosaurs or disney.
And ABDL threatens that because of sex, not just ABDL though, I think most people will never accept anything that sexualises anything that they associate with childhood and their own innocence too, like DDLG. Because I think a lot of people do yearn for the innocence of childhood to some point, it is a source of comfort for them, and that threatens that for them too, or at least makes them uncomfortable. And for some ABDLs I think it is hard to be rejected while agere is accepted, so they try to say it is the same, but realistically, sexualisation is the issue people have with it, and if you take that away like with agere, then it isn't the same because the issue people have ceases to exist.
There are people who openly engage with both communities and are accepted through like Kidden (YouTube/TikTok), as long as they're respectful of boundaries and keep it PG in the agere spaces most age regressors welcome them with open arms, so don't feel too upset, really I think people are just trying to protect themselves, their own identity, safe spaces and experiences
Ultimately, these are imperfect labels, there are people who may have very similar needs, experiences, feelings, and boundaries that use opposite labels. I think the imporant thing is that everyone just respects others experiences and understands that even though they don't understand or haven't experienced them, it doesn't make them invalid.
I hope that makes sense, it was more of a thinking out loud!
Always be true to yourself. 
