Do I have to get something out of it?
Yes, or you wouldn't bother.
Rather than address him, the one acting out, you feel it makes more sense to address the one addressing him. What is there to gain from defending bad choices?
Perhaps I don't agree with the method of him being addressed. Do I have to address him as well to also have a valid point about his being addressed?
How would you resolve it in this case if I weren't otherwise replying to him, by omitting your feelings to the point of neutering the message, or by simply not replying at all?
From what I've seen it'd be largely the same without the bravery to be insulting, which I guess in this case might stand out over how he keeps saying you're horrible to the point of you feeling the need to prove otherwise (unless I'm confusing him for someone else, this is the one who keeps being on your case about Steam right?).
I personally believe in the full spectrum of conversation, people should have the room to be insulting to spur out further banter instead of feeling like they can't be that way over some sort of Ableism or whatever. In that sense I see more value in your Steam history with the guy being used as a tool over how it's at least not dishonest, rather than your invalidating that form of communication entirely before distancing yourself from it.
On a somewhat unrelated note, this is probably where the 'White Knight' accusations others have made towards you comes from. To me it looks more like an aversion to tense situations and a general need to projectively defend 'The Weak' regardless of their character, but I can kinda see how others would confuse it as if otherwise.
If you can excuse outlier behavior, then this is my excuse.
Starting to think you're talking moreover a restlessness rather than anything about him.
Sounds like more invalidating.
Am I wrong though? I don't really see your motivation here beyond your habits.
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