The most technically proficient trumpeters in past came from Cuba. Raphel Mendez is one, though as far as I know, he did not play jazz. He ran technical rings around everyone else I have heard.
A modern example of a trumpet 'genious' is Wynton Marsalis. His (blindingly great) technique is never used to show off- and always compliments the music. So many young trumpeters I have heard are outstanding, and show great promise.
Miles, on the other hand, decided to (as they say) 'lay out' (i.e. not blow his horn) when he realised that his techincal ability was too challenged. Credit to him in this respect.