You make a big assumption when you say that all those people want is to scream all day. Why do you say that? Nobody ever said that except for you. So you're saying that anybody who isn't able to play from double pedal C to triple C the very first time they touch the trumpet is basically screwed? God forbid that you would ever try to improve your range, why.. that would make you unmusical!
You say the DHC is easy? Well, not for some people. You can be as musical as you want, but if you are not physically able to even play the notes, then you are still going to sound terrible. That is the order: Learn how to just play the friggin' notes --------> play them musically. It makes no sense the other way around.