Hey, I heavily disagree. I don't have the energy to format this post like I usually format my stuff, but I'll try to explain as best as I can why I feel this way without being disrespectful, and hopefully you can understand or at least respect me back.
First of all, you say it's not ageist or dehumanizing, but... It is, though. You saying "nuh uh" doesn't make it not true. You can hold the opinion that it's not damaging, but that doesn't make it not damaging... Does that make sense?
Second of all, DNIs are stances disguised as boundaries. When an anti says "radqueers DNI", and continues to interact with radqueers, that's because what they meant to say is "radqueers are not welcomed here". That's an example, but it works the same way. When someone says "minors DNI", what they actually mean is that minors are not welcome there.
And third of all, and most important,
Policing other people's actions is not a boundary.
You can be uncomfortable with someone talking to you directly. You're absolutely allowed to stop a conversation if you learn someone is underage. However, you don't get to decide if they look at your blog, like your posts, or reblog your posts. That is an action they are taking, and as long as they are not forcing you to interact with them, that action has nothing to do with you. You cannot attempt to control other people's internet experience and claim that as personal defense.
Now, let's put all of those together, yeah?
MDNI stances are attempts to push minors out of certain internet spaces. It does not matter if one blog believes that what they are doing is in individual scale, because when 90% of NSFT blogs have this "boundary" in place, it is no longer about personal comfort. Minors who follow this rule have nowhere to go to explore their feelings safely and feel a sense of community around them, and minors who sneak around this rule are still impacted by what it implies: they are not welcome. This is not their space. They are wrong for doing this. Not even mentioning things like moral OCD, that sentiment alone can really screw up a person's perception of their own sexuality from a young age.
If the point you're trying to make is that minors should break this "boundary" silently, without making themselves known or heard, not only does that render the "boundary" pointless, it also is extremely telling of what you believe minors should be like. Smaller. Quieter. Less noticeable in adult spaces, for the sake of adult comfort. And that is ageist.
I hope you can understand the points I am trying to make. And I hope you do better. Because someone's age alone should not be a determining factor in if they get to exist somewhere. Adults already control kids enough, we do not get to tell them to go somewhere else just because the idea of them existing near us makes us uncomfy.
