Ford did look a bit old there. Still, if you recall the end of the movie, when Indy and Marion get married, there was a clear indication that they would be continuing the franchise with Sharia LaPoofda taking over the adventures from dad, much as Indy continued Henry Jones’ work in the earlier movies. As yet, nothing even whispered about the next installment.
Meanwhile, Harrison Ford has done more movies than this twerp since then. He was even acceptable in Star Wars VII.
I agree that Shia, for whatever reason, has killed his Hollywood career. In the hands of an undisciplined individual, $10 million dollars does not last very long.