There isn't any virus in game files, I downloaded quite a few games from Itch and sometimes warning appears about "Unknown author, unauthorized software" etc., game file I uploaded is clean but I understand your concern, thanks for commenting.
It's not a lack of confidence. I download game from itch like every days. But last year I've got hacked (not from itch) and after that my pc got multiples viruses. So if my pc said "No" it's gonna be a "No". Pretty disabling for me but I'd rather safety that fun.