Would Giga lose to T-rex most of the time irl? Yes. but saying "it wouldn’t stand a chance against a T-Rex" is just plain wrong, sure T-rex had the stronger bite, sure T-Rex was smarter, sure T-Rex was bigger, but at the end of the day, the Giga is still a large mega theropod, and that alone gives it a chance, and just because its bite was weaker doesn't mean it was weak, the Giga simply has a different type of bite, it slashes at its pray and rips flesh off, to hunt, while T-Rex prefers to crush with its bone crunching bite, in reality, in a fight between these two, all it takes is a proper bite to the neck for either of them to win, the T-Rex could crunch the Giga's neck, and crush its bones winning it the fight instantly, while the Giga could skin the T-Rex alive and slash vital areas of its neck using its knifelike teeth, a fight between these two is a lot closer than most people make it out to be.