Not really sure about your first question but I don't think there's even a debate as to whether or not EDM producers are musicians. Technology and computers are involved in almost every genre now so to say that it isn't music because computers aid the process doesn't make any sense. Most producers are well versed with musical instruments anyway and incorporate piano riffs or something into their production. You can't just start making/mixing music (well) without any musical knowledge.
The average bedroom "DJ" might not be considered a musician because they're just tweaking and altering music that isn't theirs, but as far as I'm concerned it's still an art form. My friends friend came with us last year to see Nervo, Sidney Samson, Chuckie, Roger Sanchez and Paul Oakenfold, and prior to coming he thought DJ's pretty much just pushed play. Soon after we arrived his opinion totally changed and he was really appreciating what's actually involved in a quality set.