I think Pitbull is a very good fighter but yeah I think if his career played out in UFC he would have been as successful. Thats not shitting on him but I dont think he beats prime Aldo, Volk or Max. And to even get to a title shot like you mentioned Lamas,, Dustin, zombie, Mendes, Conor Volk, Max, Edgar, that aint easy.
I think he probably would have gotten a few title shots but theres a real legit possibility he'd have been a consistent top 5 guy who never held the crown. But you also can say timing is key and maybe he gets a shot when Aldo is declining a bit and instead of max Pitbul gets the shot and wins. Thats possible but even if he did win title I def dont think he'd have been the king in UFC like he's king in Bellator basically being champ for years and years and face of the div.
Think even biggest UFC haters, Bellator fans, Pitbull fans would admit that much.