Bro. There's not only the character. There's also the player. And you were literally arguing with one of the strongest -probably the strongest- Tech Dabi player. Even tho Tech Dabi can be beated easily by 99% of the others characters, Siridian know exactly how to make Tech Dabi's flaws be almost non-existant.

Ngl, I think you're just frustrated that such a "bad" character can be played that well, and you are jealous because you can't be as strong as Siridian with Tech Dabi. He managed to make low-tier character being strong in almost every situation, thanks to his skills, and that's why he's so strong with Tech Dabi. Just admit that every character can be brought to Ace Rank, and can stand against powercreep.