Hope everyone's doing ok with the COVID-19 pandemic going on.
Now, down to the topic at hand.
There were several posts made in the past 5 years about hybridizing the 2 largest carnivorous dinosaurs in the franchise into one animal.
Might seem like it was an original idea that started here, right?
I doubt it now.
Prior to Colin Trevorrow coming on board to direct Jurassic World, the big carnivore that would be more dangerous than the T.rex would have been called the "Malusaurus", a completely made up (but in-canon scientifically valid), genus of theropod.
Why is this important to the topic? Take a look at its concept art.
Who else thinks it bares resemblance to both the T.rex and Spinosaurus?
Klayton Fioriti, the foremost expert on Jurassic, agrees (starts at 3:33): https://www.youtube.com/watch?v=Y90dKswP948
There you have it ladies and gentlemen. The Spinosaurus rex was already a thought-out concept for Jurassic World, before I learned of any ideas about it in this forum to make hybrid fight stories. It was just under a different name.
I see it, I guess the idea of a hybrid clicked in Colin Trevorrow's mind when he saw the concept art of this beast.
No, it was because making a made-up dinosaur made no sense in moving the franchise forward.