The fact that only Lucas has so far saved the world from Indiana Jones IV is another reason why he should be praised. There is nothing worse in the film world than remakes, but the second place in the hierarchy of idiocy is occupied by belated, unwanted sequels that no logic accepts (especially when you have a self-standing trilogy that opens and closes itself perfectly), that only a couple of "fans" actually demand, and that only gets considered because it's easy money. There are about four exceptions where a sequel was actually good enough to be comparable to the original,
there are exactly three cases where the sequel was better (Godfather II, Bride of Frankenstein, Star Trek II), and there are a few cases where a sequel is so different that it makes an excellent film on its own (Return to Oz), but 99,99% of the cases are cash-in trash. The Indy IV crowd probably consists of the same ones that are now wondering "duh, me want know when Peter Jackson shoot Lord of the Rings IV, duuh". (Of course, half of Hollywood executives ejaculate over that very same idea, too)