it would help itchio traffic by an incredible degree
Now, if you can convince Itch of this, they would have a bigger incentive to implement it.
most people search through by tag
Is there any reference for this?
Of course this is plausible, as browsing for tags will give you games that have at least one aspect you are looking for. But this does not mean, that people would also want to browse negative tags. I know that Steam has this feature, but I never ever heard of that feature before the discussions on Itch. I even had to look for the feature, because it its not that obvious how to do it. If you click on a tag on Steam you do not get to a place where you can negativly select other tags.
A game I like is Backpack Hero. It has these tags
Role Playing, Card Game, Strategy, 2D, Cute, Deck Building, Dungeon Crawler, Pixel Art, Roguelike, Roguelite, Turn-based
Is there a scenario in which I would find this game better/faster/whatever with the use of a negative tag? There do be scenarios, where I might miss this game, because I used a negative filter. Maybe I dislike "cute" games and negativly selected "cute".
I wonder how many people even know how to use - on a regular, non tag based search engine. Many people do not even grasp that you can enter freestyle tags in the browse box, or that there are two search boxes on Itch. It took me months to realize that. But I was used to Steam, and tag searching is not a big thing there, at least not for me.