Background of the Term DISRUPTIVE
In an article
in the New Yorker (which is a remarkably cognizant recapitualization of how and on what motivation the theory was developed), Christensen is said to have referred to LOW-END products which would represent a NEW TECHNICAL STANDARD as “disruptive technologies,” because, rather than sustaining technological progress toward better performance, they disrupted it.
Michael Raynor also observes
the manner in which this same phenomena became the basis for Christensen's original thesis, wherein the changing of the dominant architecture for disk drives coincided precisely with the reduction (rather than an increase) in traditionally measured product capability.
As to whether Christensen could have selected a more definitive (and less prone to abuse) name for the phenomena - he often says that he would have had he known the long-term implications. But then that goes for much of what us humans do, does it not?
Hope this helps.