It's true that we were not a soft team last year, although note that in the NHL playoffs physicality is typically turned up in the first round and peters out as guys get worn out, so teams eliminated in round 1 will naturally over-index on hits/game compared to the teams that go further.
Thats fair, although I do believe our first series was the most physical one (could be wrong), and we would've likely continued down that path considering who was waiting for us had we made it out of the first round.
Also note that Jarn only hit 20 goals once in his career, so calling him a 15-20 goal guy is overly generous. Typically he's in the 12-15 range. But that's not the chief complaint against him, the chief complaint is that he's a ghost in the playoffs (5 goals in 93 games).
He typically hovers around 15, but I can agree that it is unlikely that he pots 20 goals again for us anytime soon unless he plays a decent amount in the top 6 (he probably wont).
But let's focus here, because the discussion isn't about the rest of the team but Jarn vs his likely replacement (ie Lorenz/Dewar). I think both of these guys can do what Jarn does defensively, I think they're both capable of hitting 12-15 goals if given as much ice-time as Jarn, but they also bring an extra element of physicality and cost half as much.
So assuming we are able to dump Jarn (not a given), why would we chose him over a Lorenz or a Dewar?
Just my personal opinion, but I was not very impressed with what Dewar brought to the table last season. I just don't see him getting anywhere near 15 goals (he was at a 17,5 S% when traded and fell back to his standard 5% with us), and his defense is subpar at best. Yes he throws hits, but if that is your most redeeming quality on a team that is already very physical, I feel like you are expendable.
I haven't seen enough from Lorentz to have an opinion on him, but sure, if he can do what Järnkrok does, replace him by all means. I've just been fed up with people pointing at him as one of the bigger problems and wanting to replace him with vastly inferior players just because they are cheaper (Cowan, Minten, Dewar, A. Nylander etc.).