One of the most baffling decisions this franchise has made, I have no idea what the impetus was to hamstring their own future movie plot potential. I’m sure if they change their mind they’ll just retcon it without a second thought though. More on reddit.com

Finally an interesting map. More on reddit.com

The continents were all still connected as Pangaea at the start of the Mesozoic era when the first dinosaurs appeared, but began to break up during the Jurassic and continued drifting farther apart into the Cretaceous. This website has a great series of interactive maps from different time periods you can look at. It's been suggested that the first dinosaurs appeared in what is now South America ( Nesbitt et al. 2009 ), but they quickly spread to all continents including Antarctica, from which we have several fossils such as Cryolophosaurus . As you suggest, dinosaur species were typically restricted to certain areas rather than being spread out around the world, especially after Pangaea became more fragmented. However, many species had close relatives that lived in other places, such as the North American Tyrannosaurus and its close relative Tarbosaurus which lived in Asia. Certain regions of the world have become known for certain dinosaur communities that can differ a lot from one place to another too. For example, the Patagonia region of South America was home to many of the largest known dinosaur species during the Cretaceous, including huge sauropods like Argentinosaurus, Puertasaurus, and Dreadnoughtus , as well as some of the biggest theropods like Giganotosaurus . Conversely, the Hațeg region of Romania (which was an island during the Cretaceous) was home to several smaller than usual dinosaurs, such as Magyarosaurus and Telmatosaurus , demonstrating a prehistoric example of island dwarfism ( article , and Grigorescu 2010 source). Finally, Cretaceous Northern Africa is known for having supported an unusual number of large carnivorous species, including Spinosaurus and Carcharodontosaurus , though this reputation may be a bit exaggerated as there seems to have been a correspondingly larger diversity of prey items as well ( Ijouiher 2016 , though still in preprint). More on reddit.com

For people who are interested in this kind of thing, the Paleobiology Database is really useful. For instance, you can search "Dinosauria" and select the Mesozoic era to see a comprehensive map of dinosaur sites and click on them to see exactly which fossils have been found there (however, the information is somewhat detailed and technical). More on reddit.com