"That might even lead to concerned publishers contacting support that the nsfw setting does not work for their game, since they can see it right there among the regular horror games..."
Again, trivially easy to add a note explaining that you'll always be able to see your own games.
Also, again, a shadowban is a punishment where a. the admin/moderators of a site decides that no one sees a user's content, and b. it happens without them being informed of this decision. Neither a nor b is even close to what we're talking about here --other users who choose to not show NSFW content will not see my game, exactly like before, and I know of the decision because I made the informed decision to label my game as NSFW, knowing full well that this filter exists and how it works because, well, I'm turning on the filter myself.