I still don't think that trade was the problem. The problem was how Reaves was used and the beefing with Ian Cole and the pining for Brassard, the way Reaves was used and how the Cole trade went down hurt the team far more.
They gave up a solid top 6 defenseman, a 1st, and a very good goalie prospect to get Brassard and get rid of Cole and Reaves because Sullivan wanted to be a petulant child about using both of them and didn't think Sheahan was enough, then he shit all over Brassard's usage and made that look far worse. They gave up a 1st, 3rd, Gustavsson, Cole, and Reaves and got back the shittier Vince Dunn, a 3rd and Brass.
Then they dealt a 2nd and 4th round pick in 2019 for Bjugstad and McCann, two players Sullivan couldn't decide if they should be W/C and used them like shit.
Bjugstad had to be moved with salary retained for a conditional pick.
McCann who Sullivan couldn't decide if he was a RW/LW/C and ghosted in the playoffs, was traded for a 7th rounder and Hallander.
1st in 2018 - K'Andre Miller
3rd - Justus Annunen - Goalie (Cole/Brass trade - Ironically, the Pens got the second 2nd rounder to take Filip Hallander)
3rd - Jesper Eliasson - Goalie (Sheahan trade)
2nd in 2019 - Turned into Vladislav Kolyachonok - D for Utah.
4th in 2019 - Eric Hjorth, who?
The Reaves deal ended up being Reaves + Lauzon for Sundqvist and Kostin (the players taken with the picks).