But there are major problems with your definition, too. Yours includes only necessary, not sufficient, conditions for disruption. Lot’s of ‘radically cheaper’, inferior products never disrupt.
Shameless plug, I wrote an article about this, which I think sorts it out well: https://artplusmarketing.com/misunderstanding-disruptive-innovation-7154ff4fe9b5
The key is to decouple the precedents from the consequences. The main insight is that disruptions come just as often from big incumbents with initially superior offerings as they do from little firms with sneak attacks.