Hollywood does slow explosions too. Its kind of a funny meta-anachronism when CGI uses the slow firey explosions that I suppose are inherited from the limitations of practical effects using gasoline deflagrations.

YouTube has shown people real big explosions (Beirut, Tianjin, etc) and how vicious they are, but you rarely see a CGI shock wave.

Rockets too, RPGs are fast but movies have them sauntering through the air.