Two head cannons, that's all I have rn.
NUMBER ONE- Dabi is just as good at social ques as Shoto, aka not at all
TWO- Katsuki is hard of hearing or going deaf but he loves all of his fans. Even more so, he loves and appreciates all of his fans that have a disability like him bc he can make them feel safe even if they cant hear, talk, move, all of that stuff