I mean it's a workaround bc there is no UI to turn this on.
I personally use excluding filters all the time, in Steam and many other programs. It's a big QoL feature for better searching.
Moreover, on this website, it's a BIG NEED feature - just open the popular games tab, it flooded completely with horror games. Sometimes I don't want to play a certain genre, BUT I always know what I certainly do not want to play. It's where this feature comes in handy.