Like, if I showed you moves and said it is the perfect game, there'd be no way to verify it.
So in some kind of ultimate sense, the proof only exists in the mind of God. That sort of thing.
I mean, ok.
But if we cataloged all the positions (like a 32 man endgame tablebase) and for all of white's first moves he computer said "it is a draw" I would believe chess is a draw, and I would call it proof.
Well, I still remember making an unkind post related to your age, and even if you don't mind, I felt bad about it.
Anyway, your evidence is very good, and I agree chess is a draw with best play, it's just the nay sayers here want the ultimate, basically unreachable, highest standard of proof.
Which is not there and will never be there. Even if it comes out chess is solved--this would not at all mean that there is 100% proof chess is solved.