The US defense/goaltending is better than everyone else in the tournament by a country mile.
All 3 goalies (and Demko if healthy) would be automatic starters for Canada and their blueline is so skilled and mobile but without giving up anything defensively.
the us forwards might be better too, imo
like you said, robertson didn't make their roster... while he probably should have, there just isn't anyone of that quality left off the canadian team.
canadian depth might be better 10 rosters down to the AHLers or whatever, but the top end US talent has clearly surpassed ours. after makar (and he's genuinely arguable as tied with hughes), 6 of the next 8 best defenseman between the two countries are american. the top 4 goalies are american. given that he's currently a leaf, stolarz as their fifth best goalie might've cracked team canada.
of the 13 forward spots, i think only four would for sure go to canadians - crosby, mcdavid, mackinnon, stone. matthews, m.tkachuk, eichel, hughes are their locks. very strong argument for reinhart, marner, point, but equally so for guentzel, brady, JTM and connor.
i think they messed up taking guys like trochek and nelson over robertson and thompson, so hopefully our depth guys like cirelli and bennett can make up any advantage they have in the middle-6.