It is not too hard a stretch of the imagination for the smaller, in relative terms, dinosaurs to be warm blooded but I remember seeing a show calculating the amount of food a warm blooded sauropad, like Apatasauraus, would need to eat and it seemed unlikely they could eat that much.
They could have been warm blooded but not at 98.7F degrees.
Each degree you drop it the less food the animal needs.
There was plenty for them to eat, but they couldn’t be fussy, kinda like any old wild animal today. :’)