Well, I forget who now, but somebody pointed out that as a program focused primarily on development, the NTDP rolls their lines better than any junior or pro team top prospects are playing for. It seems that Sanderson rarely saw much more than 20 mins per game. This may have some impact on his numbers, which are similar to some other NHL stars who have come through the program - almost identical to McAvoy's.
There is also this:
2020 Draft: Sanderson could rank among best-ever defensemen at NTDP
The NTDP's defense coach over the past nine seasons says Sanderson is top three he's seen come through, from a group that includes Seth Jones, McAvoy, Werenski, Hanifin and Cam York.
While I appreciate the value of stats for evaluating prospects, I prefer my own eye test over both stats and media scouting services. Not because I think I'm so great at it, but it's just like growing your own vegetables or catching your own fish vs buying store-bought. It's more rewarding and something you can stand behind.
As I said after the winter Five Nations, I've been a big fan of Sanderson all year, but that was the first time I started to question if he might be better than Drysdale. I thought I'd use the U18s to settle the question. For now I still have Drysdale ahead, but I'm gonna watch some games from this site Rafi posted, and maybe go back and watch one or two more of Drysdale from international play, and then make a final decision.
Regarding the unspectacularness of a guy like Sanderson, the one thing there's no denying is his skating gives him an element of dynamism. Rough comparisons I'd use would be Jake Trouba, Cam Fowler, or best-case scenario, Roman Josi.