I do get this take, but I feel like it ignores the context a little. He had a strong camp, and looked great within those 6 minutes. It's sort of hard to judge his game too much in those 6 minutes, as it could have just been a good night for him where he may get exposed on D any other, but he was making good decisions on D, facilitating with the puck on his stick, and playing in all situations. And remember, this was an elimination game against a very rough and tumble team in Minnesota that came to play for their lives. This was the least sheltered game possible to have his debut in.
Everything within those 6 minutes was indicative of at least bare-minimum NHL readiness to me. His body and skating just needs to hold up, his processing of the game at that level is there.