T-rexes and other carnivorous dinosaurs who are of similar build are either intentionally fake or had been created with great misconceptions with no one ever questioning the biomechanics. Dinosaurs of that build cannot eat healthy four legged herbivores of similar size to them because they would get their asses kicked or gored since they don't have no real defensive or effective offensive mechanisms due to having near useless arms and the fact they have to stick their head out first when wanting to bite or run at full speed (which they can't as admitted by science articles) so they would have to resort to eating animals who are too small to fight back which then would require t-rexes to eat alot of small animals in order to maintain the necessary calorie intake for their bodies to survive which in of itself will be a difficult task since they will have to compete with their own kind (and other carnivores) for those animals in addition those animals can hide or find shelter that t-rexes cannot penetrate or reach. In addition t-rexes would be prey to various carnivores due to their long tail that they need for stabilization and their massive blindspots. By evolution standards these creatures are malaldaptive to the point that they wouldn't be able to live long enough to even reproduce even one generation due to these mentioned factors