Not sure if it's true, but I read where a science fiction writer, forgot who, maybe Orson scot card, or another one, where among the articles he wrote he commented that humans don't reproduce fast enough to be a viable food source. Though a temporary food source could be ok. And some societies may not care about viable food sources.
It reminds me of an ooold comic book series, based on an idea that Leonard Nemoy had. Primortals. Though I've not read much of it, the publisher, Tekno comics, went poof and didnt' last long. But I think the dinos were uplifted by aliens, & removed from the earth, and are anthro. One evil one decides to return to earth to conquer it.