Yuup this entire post smells very fake

Why do you think that?

I don't doubt that the scenario described here with a teen demanding their mom's deadname tattoo could happen, it's the most teen thing in the world. Teens are incredibly self absorbed and if it's real then I have hope they'll grow out of it, and not that they are enabled to get worse. I don't think this post is real, though, and it's largely just something about the way it's told. Like the commenter above me said, the AITA sub is one of those creative writing exercise subs.

To give an example, though, I think the dismissal of the mom's depression is suspect. The woke crowd is very much about virtue signalling, and how much they care about things like mental illness. I think the author would either not bring it up out of embarrassment (if they don't believe their mom has it, they could simply say "she gives weak excuses about not having the energy", that way they don't risk questioning someone's mental health), or they would give reasons why the mom is faking it (she goes out to see her friends all the time/author hasn't seen any of the symptoms she describes/she's a narcissist with a history of faking things for attention) and then use that to make themselves even more the victim.

The cousin siding with them does make the story sound more realistic, but the style, something about it, it just feels like someone wrote this as fiction.

The style is off, I agree with you. All of the creative writing on subreddits like this (including r/relationship_advice) have the same flavor and tone.

To give an example, though, I think the dismissal of the mom's depression is suspect.

I had the same thought. It seemed like it was included to try to muddy the waters. People turn to AITA because they want to be right, so why include something that would make the audience sympathize with the mother only to get a dismissive "pssh, which, whatever" from the author within a couple sentences.

Could definitely have happened, but that was curious to me as well.