Yeah, it's not like DT has never used electronics in their music. They've always had a keyboard player, which is by definition, electronic music. And then they have used sound sampling plenty of times before. And on ADTOE, Petrucci programmed in the drum tracks while they were looking for a drummer.
I mean, it's still 100 times more complex than a lot of the crap that passes for modern-day EDM (which is mostly ghost-written anyway). But I don't think Petrucci meant electronic music produced by humans with that comment...I think he was more talking about music that was composed by a machine algorithm (or maybe a cut n' paste pop-song algorithm that the record industry pushes on people).