

Glad you already learned this is probably nonsense. The wrong reasoning is very similar to much thought about overpopulation. The amount of people that makes for a place to be overpopulated is a function of how societies work and the technologies they have at hand. One extra issue there is that improvements in technology usually lead to population growth, so much progress gets cancelled out.
The dinos are back, but of some species, every generation is smarter than the last, until they actually start speaking. Because they had a super civilisation, and their scientists encoded the key to rebuilding their civilisation in the DNA we found. The next generation becomes smart enough to invent a time machine, and try to manipulate us into going back in time to prevent the comet strike that took them out. Joke’s on them - they were in fact aware of the comet strike, but as we travel back in time together, the human part of the crew sabotage their Armageddon mission and make sure the strike actually happens, to pave the way for mammal domination!