Hello! I'm glad that this post is sticky, but... why not just add this feature already? It's been like this for at least 5 years. Here are some related threads I've found on the topic:
https://itch.io/t/2020007/filter-out-tags - 1 year ago (links to next)
https://itch.io/t/653769/can-i-exclude-horror-games-tag - 3 years ago (links to next)
https://itch.io/t/160014/can-i-use-exclusion-filters - 5 years ago (an admin actually provides a URL suffix, so obviously there's a way to fix this)
I know NoTimeToPlay (tagged as a moderator) has been answering all of these threads with "I can't do anything about it", but we also have seen Leafo respond to this issue with a temporary and limited solution. Surely he, or other developers of itch.io can expedite this issue so that itch.io isn't seen by non-developers as a horror games platform..