This is a flawed argument because Synths, while not to everyone's taste, does not completely change the activity. A band that moves around on a field is a marching band. A band that stands still and plays a concert is a marching band. While a marching band/corps, with or without synths, is still a marching ensemble.
As for the second statement, no...no it isn't. It's honest. The music on the field may not be to some people's taste, but it doesn't make it not music. An apple with it's skin removed is still an apple. It may not be to your taste, but it's still an apple. And arguing that it isn't makes that particular "opinion" absolutely asinine.