You're correct.
I did a quick once through the league looking for players under < 170 last year.
Johnny Gaudreau .. 157 lbs.
Paul Byron .. 159 lbs.
Tyler Ennis .. 161 lbs.
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Brendan Leipsic .. 165 lbs. (only 6 games)
Yanni Gourde .. 168 lbs. (only 2 games)
I found only 3 NHL regulars and 2 (post TD) subs that played in the NHL last year under 170lbs.
Marner is a special player so hopefully he can make it as rare exception
, as its not the norm despite the league getting smaller recently. The average NHLer is 6-2/201'bs (in 2016).