Yeah, it's one of those weird things where the NHL only counts 'streaks' if they occur in the actual team's games -- so, missed games means your streak is over.
I think Gretzky's famous 51-game point streak was actually 60-some if you go back to the end of the previous season. And Neely would have a 50-in-50 goals season if not for injuries... Jari Kurri, also, I think, in 1984-85.
But I can also see it from the NHL's/RuleBook perspective. If it starts to be a thing where a player plays 8 games, then misses 30, then plays 25, then misses 20, etc. -- is it really a streak if he scored in all his games? I dunno. So I can understand their logic.
But I agree that it should still count as a 'streak' if the games all occur in one, single season, regardless of a player's missing games to injury. So, I'll personally give Hall his 16 games...
Hall is a great winger and the Oilers certainly could have used his offence this season. But that trade was obviously not made in a "1-for-1" mentality -- it was a trade to begin changing the Oilers' team culture. Last year, it appeared to have worked well (team went from 25th defensively to 8th when Hall left); this year, not so much. But I would never decide that a trade was "won" or "lost" only a year or two after it was made, especially when it involves two young-ish players who might have 8-10 good years left.