Any bearing surface needs lubrication. Some lubricants last longer than others. Contamination occurs regardless. The challenge is to extend maintenance intervals for maximum effectiveness with minimum effort. The systems in use in brass instruments work well when not neglected, and synthetic lubricants help keep the mechanisms trouble-free for a longer period of time than conventional products do. The same result of neglect affects devices with moving parts, whether they are trumpets or automobiles. Dry lubricants seem to work particularly well, firearms and chain-driven devices being a couple of examples that come to mind. How well dry lubricants would work with trumpets, since part of the requirement is not just lubrication, but sealing as well, I don't know. I would think that tolerances would be crucial. As for instrument design, evolution, exemplified by the use of computers has improved musical instruments, has worked quite well so far. Revolutionary change has already occurred; just listen to the electronic sounds being synthesized today. You don't need a trumpet player, or even a trumpet to get an authentic sound these days! Personally, as far as brass instrument design goes, I say: "If it ain't broke, don't fix it!".