On reflection the exchange approached equilibrium by the end. But I still feel no change would have taken place without extra effort by Tibbs. He placed himself repeatedly at risk of bodily harm or death just to stay and solve the case. Gillespie chalked it up to a need to prove superiority, but that doesn’t strike me as good enough motivation to take such risks. Tibbs wanted justice regardless of who committed the murder, while Gillespie was ready to call it a day every time they found evidence against one person or another. He pretty much came around only once proven wrong. To his credit he ultimately defended, Tibbs, but only when forced into positions where he had to choose one side or the other: Tibbs and Endicott slapping each other, the hoodlums circling in on Tibbs.
That’s not to say I wasn’t sympathetic toward both characters. I just found Tibbs’ task a lot more Herculean in nature.