Dermott hasn't had a chance to play much on special teams so far so we can only really look at his even strength play.
I won't bother to compare him with guys like McAvoy, Provorov, and Werenski, who all face top competition on top pairings.
Legend:
Letter Grade qoc = Quality of Competition measured by opponents' time on ice, Converted into Letter Grades for simplicity
p60 = points per 60 minutes
CF% = Corsi For Percentage (i.e. shot attempts for percentage)
xGF% = Expected Goals For Percentage (i.e. shot attempt percentage adjusted for shot quality) - this stat is already adjusted for zone deployment and game score
In Brackets = CF% and xGF% relative to team
Chychrun (19): 18:21 (B- qoc), 0.78p60, 46.1cf% (-3.8rel), 45.9xgf% (-0.8rel)
Sergachev (19): 13:40 (C+ qoc), 1.25p60, 52.8cf% (+0.8rel), 54.0xgf% (+1.8rel)
Chabot (20): 14:32 (C+ qoc), 1.03p60, 46.9cf% (+2.0rel), 46.0xgf% (+0.9rel)
Hanifin (20): 16:55 (C qoc), 1.20p60, 55.8cf% (+3.5rel), 56.8xgf% (+4.1rel)
Dermott (21): 15:53 (C- qoc), 1.27p60, 53.5cf% (+4.2rel), 51.9xgf% (+3.0rel)
Chychrun is the toughest one to judge here because he's being forced into a bigger role on an awful team while being the youngest on this list. His numbers are worse than the others but I don't think it's a fair comp.
But the other 4 seem to me to be very comparable across all those numbers. Note that Dermott is actually only about a month older than Chabot and Hanifin.