Funny seeing so many people pointing out how absurd it would be to have Dinosaurs in the game in the light of the fact that there's, in-fact, more than twice as many in theHunter as in theHunter: Primal There's this thing called "Birds" which happened to fall well within the
Dinosauria clade. But I digress since it can be attributed to pure semantics.
That said if realism is the main concern, oh well, how come the world's map looks nothing like that of Earth?
Why can you hunt plains bison in Alaska?
Why the moose in Alaska, Sweden and British Columbia are identical? By the same token why are the feral hog and wild boar treated as different species in the game?
Why the coyotes in game are at least comparable in size to the heavily hibridized Eastern Coyotes in spite of being only found in North Western USA maps in the game?
Why there is no red fox in any reserve based on the United States in spite of having a very wide range throught most of North America?
How come the only cinegetic native species in Australia in-game is the red kangaroo?
How come there's no wild boar in the French Alps?
Where are ALL the juvenile animals in the game, did all those large fully grown and usually pretty old animals popped out of the dirt (obviously not, the game spawned them but that's besides the point)?
Why the white-tail deer in Louisiana and British Columbia are identical?
How come animals don't suffer of any mommentum after being shot while they were running at full pelt?
Why the player character can't swim in spite that over 50% of all USA citizens can swim and around 70% of all European citizens can also swim?
Why the character in the game can't jump?
Why all bow's in the game (other than crossbows, obviously) are automatically reload after shooting?
How come animals misteriously vanish after being collected?
The list goes on an on. The best thing about it however is that for all we know all of the reserves in theHunter might be on Primal Eden. A closer look to theHunter Primal's minimap shows that the GPS image is cut off irregularly as if it had been done deliberatelly to not show the rest of the landmasses in the island. And the well before the reserves were added we had no way to now that the planet in theHunter had a "Europe" and "Oceania" continent.
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On a sidenote you are right about one point though, when it comes to models the animals in theHunter are much closer in anatomy to the animals they represent than those in theHunter: Primal. But if the game is set in an alien planet anways
This is debunked for years now 
