The fact that Dabi shows off his scars and wears revealing clothing can definitely be interpreted as him wanting the world to see how much Endeavor fucked him up and I do think that's one of the main things he wanted to convey by showing his body off
But hear me out on another prospective with this whole situation.
The fact that in the first season he wore clothes that hid his body more and the fact that when he was a kid he hid the fact that he got scars from his father leads me to believe they could be a way to show his openness and his real self.
When he first got the scars he hid them as to not seem weak and less then by Endeavor, later on when he was a teen and then an adult he got more and more scars but he still hid most of them. If they do connect to openness and his real self it would make sense, he wasn't Touya anymore and at that point Dabi was repressed too, he didn't really show his real emotions until the live stream where he exposed Endeavor.
His scars were on display for the world to see and that was a turning point, once he identified himself as Touya he became much more comfortable with showing his real self and we could see that, gradually, his outfit began to show his body off more thus exposing and showing his willingness to display his real self.