You are aware Johnsson has 19pts in his last 25gp, almost entirely in a bottom 6 roll (meaning 5-12 minutes a game with no Matthews, Marner, Tavares)? That is in line with Carolinas hottest players right now over the same timespan.
In his last 35gp he has 29pts (12:52 TOI), as compared to Teravainen 36pts (17:54 TOI), Williams 27pts (17:15 TOI), Ferland 21pts (14:38 TOI) and Niederreiter who has 15pts in 15gp since joining Carolina (18:31 TOI).
And his most common linemates this season have been Connor Brown and Par Lindholm, which I'm sure you knew, because you said you liked him.
I'm very aware of what he's done as the Leafs are my 2nd team and I watch them often. I've also learned over the years that a guy that has some success on a small sample size on 1 team doesn't mean it will translate to another team in a different situation. Elias Lindholm is on pace for 95 points where he never had more than 45 in Carolina. Jeff Skinner had 24 goals last year and is on pace for 49 this year. Eric Staal had 54 points and 33 points (63 games) his last 2 seasons in Carolina and then suddenly in Minn he was a 40 goal scorer again. Toronto has scored 221 goals on the season and Carolina has scored 177. It matters.
Being "in a bottom 6 role" has pluses and minuses. He gets less ES TOI and not as good line-mates, like you said, but he gets much more favorable match-ups as well as teams are focused on Tavares, Mattehws, Marner first and foremost. Maybe Johnsson would have the same success if he was inserted into the Canes line-up as he is having in Toronto, but people assuming that will automatically happen are making a flawed assumption IMO, that's my point.
And the "no time with Matthews, Marner, Taveres" isn't quite accurate. AT ES (per Natural Stat Trick), of his 14ES Goals and 13 ES Assists:
- He's got 4G, 4A with Matthews.
- He's got 2G, 6A with Tavares
- He's got 1G, 4A with Marner
Like I said, I'd like to have him on Carolina, but personally, if he came to Carolina, I'd keep my expectations in check until I saw more.