This wasn't a mistake. To clarify, Wirehead's format is very similar that of a visual novel (at least in terms of gameplay, or lack thereof). It's really a movie with limited interaction, rather than being a "game" per se.
As for the ones already on the site, the ones you referenced were all accepted a long time ago under different rules. We generally no longer accept these kinds of things.
We felt it was very similar to how a visual novel is, hence why it was rejected as such.
As a side note, just because something is on the site does not mean we will accept things similar in the future. The four games you pointed out were all taken in 2017/2018, when we were not as stringent on game requests. It is likely they would be rejected if they were submitted today (though I have not watched them to see if this is indeed the case or not).
It's mostly hit or miss when you request a game. All of mine have been rejected, though I have seen games just like the ones I request added. You just have to hope you get good RNG, just like in speedrunning lol.
I guess you're right. It's not luck, but rather how well-known the submitter is. I submitted the Jackbox Party Pack twice, and it was rejected for being a multiplayer trivia game. Those were the exact words.
Then SummoningSalt submits it and gets it approved no problem. I guess it's my fault for not being famous. :]