As far as I'm concerned any piece of equipment that can used to create music is a bona fide musical instrument in it's own right.
There's a fair bit of snobbery about DJ decks, sampling software and the like from 'proper' musicians, but then apparently 'proper' musicians used to look down on electric guitars and keyboards, in the erroneous belief that those instruments somehow did most of the creative work by themselves, with minimal user input.
I suspect that something similar is going on with the newest generation of instruments, but it will pass.