It’s not that it doesn’t show up at the top, it’s that it doesn’t show up at all. This is something anyone can easily verify for themselves. Write a pro-Trump tweet in response to Trump, and watch it get removed from the comment chain. The tweet itself won’t be gone, but it will no longer be part of the comment chain, meaning that people who look at the responses to Trump’s tweet won’t see it. They’ll only see negative comments.
You think Trump’s tweets can get >100k likes, but no positive comments? Get real, kid.