I don't think you're going to find a consensus opinion on this.
I think an NCAA Division I team, even a national champion, is going to have a wider talent gap from top line to fourth line, first pair to seventh D, and starting tendy to the guy who never gets in games.
Fourth line/third pair/backup goalies in the ECHL are generally far better than the guys occupying that spot on the depth chart in college.
But put an NCAA Champion against the worst team in the ECHL, and they'd handily win a best-of-seven series.
The teams that are at the bottom of the ECHL generally have bad coaches, coaches who can't recruit, guys who are a problem in the room, or all three.
An NCAA champion has more top end talent and doesn't have those problems.