Show me advertisers who are happy to monetize on this exact content then.
You also have advertisers willing to target the outrage crowd, so they would also stand to gain from the post.
Not all advertisers care about the things that advertisers from companies like Disney or the NFL care about.
From there it has spread to numerous other brands like Moon Pies, Sunny Delight, etc. Many snack and food brands were highly visible early adopters of this iteration of internet culture as a way to rep their brands.
So I ask again, show me examples of advertisers that enthusiastically advertise on shitposts.
Your own chosen example was Elon Musk recent twitter history. Debating the difference between your chosen example and Dennys to identify an obvious principle that distinguishes them is asking people to play calvinball with you.
... and I say this as someone who agrees with the argument that twitter is deeply toxic, that it systematically rewards, promotes, and monetizes toxicity, and that in this case Elon was behaving in a manner which within the abhorrent norms of the overall platform. [Though, I'm sure Mr. Gates will be fine, and that ultimately the comment mostly just makes Mr. Musk look bad...]
But having a different opinion on that doesn't make someone a killjoy. Someone isn't humorless because they think that mocking someone's appearance like that-- particularly outside of special context like a comedy club-- is gross.
Humor is very hard to monetize.