He had 27 last year and 19 this year with a shortened season. If you take his career G/GP and put it over 82 games, he's averages out to a 25 goals scorer. And again over the last 3 years at 5v5 he's one of the top 20 goal scoring LW's in the NHL. He has more 5v5 goals than guys like:

Matthew Tkachuk
Rickard Rakell
Jason Zucker
Chris Kreider
Gabriel Landeskog
Mike Hoffman
Filip Forsberg
Taylor Hall

Even if you want to push it to all situations, he's top 30 in goals scored over the last 3 years in all situations. This is with him not getting steady PP time and when he does get PP time, he's option 5 because the Bruins #1PP unit has/had Pastrnak, Marchand, Bergeron and Krug as the other 4 guys.