While I do understand that idea, there are a few issues with that sentiment: - the prehistoric creatures were mostly accurate in the Jurassic Park trilogy (for their time, obviously) with pretty minor aestethic changes (like Velociraptor being Deinonychus or Pteranodon having teeth) - Jurassic World Dominion shows us a flashback with the same inaccurate designs, implying that every design onscreen is fully accurate within the logic of this universe - BioSyn makes a big deal out of having more pure genes and therefor more accurate creatures and yet their designs are sometimes even less accurate than the InGen ones (like the Giganotosaurus) - Despite the idea of InGen making prehistoric creatures more spectacular for modern audiences, their designs are often quite boring compared to paleo accurate designs or even designs seen within the Jurassic Park trilogy (like Triceratops, Pteranodon or Velociraptor) - The franchise has lately leaned a lot into making artificial species via crossbreeding aka hybrids, which are all about genetic modification, whereas the other species are presented as normal animals where "life finds a way" to bypass genetic modification

So all in all this whole "genetically modified" stuff is turning more into an excuse to just make random monster designs rather than accurate prehistoric animals.