It’s less that they have something against them. More it goes to the back of the queue instantly I think for what needs to be checked as there’s no indication anything new or original has been added. But like you say I’ve had them feature right away before. Just luck at the end of the day if I mod happens to check it straight away.
But similar to gifs. If you use a clip from a YouTube video. It gets featured almost instantly as it jumps right to the front of the approval queue, as there’s a verified safe link attached to it.
Also they have some memes feature instantly if you use one of the 60 popular templates at least, if not all of them.
If the system doesn’t pick up any bad content in the text and there’s no images added. To save time. I see some slip through though.