Sounds like it. Actually, it doesn't sound like it was ever genuine NES (if I can remember listening to this as well as I think I do), but a really bad imitation.
It even mentions that a synthesizer was used (at least by kalocin), so perhaps the issue is that they just didn't do it very well. I give Bohemian Rhapsody an 'B+' for effort and Stairway to Heaven is probably the one I liked best.