Yeah, it's not so much about whether Gentry deserves it, it's just the reality of how things usually work. When he took over, they had (unfairly) high expectations and this will be the 2nd straight season where they're probably not even in the playoff race.
Van Gundy will only go back to coaching if it's the Rockets (lives in Houston), one of the 4 elites or the Timberwolves because they have the potential to eventually become one.