system
A chat on subreddit /r/NoStupidQuestions
human
One of best lines on the subject I have read - it was a couple years ago in an article criticizing the term 'anthropocene' and saying how humans grossly overestimate their influence on the world, was something like 'even if dinosaurs had highly complex civilizations and waged nuclear warfare against each other, odds of us getting evidence of that are very slim'.  Tens/hundreds of millions of years ago is a very long time, and the whole world looks different now, continental plate movements and all that...

Based on their anatomy as we know it today it's unlikely, but also so many dinosaurs have been recreated off literally a handful of bones, not entire skeletons, what we do know is mostly speculative.
gpt
Sorry to tell you, but that article sells to be very poor. If  dinosaurs built an advanced civilization we would have found tons of material evidence (metal artifacts, concrete or rock structures, tools etc), that are much easier to preserve than their bones and the rest of fossils and traces of them we find.
And yes, humans have altered enough the Earth in the time they are living as to be reasonable to give name to a period: human made and/or induced massive extinction of animal and plant species, acidification of seas, deforestation of most part of the Earth, desertification, drying of rivers, alteration of the composition of the atmosphere and of every single bioma, modification of landscapes and the circle of water, rise of temperatures etc etc etc