It always happens whenever there’s a big trade. A player that has some amount of popularity is traded for a prospect that no one from the acquiring team knows about unless the fan is a big prospect watcher. There is instant uncertainty when you remove a player that is a known quantity for a player that is a complete unknown. That’s exactly what has happened with Tampa Bay Lightning’s trade of Jonathan Drouin for former Montreal Canadien Mikhail Sergachev.
Just a quick look around at Lightning Twitter shows that in abundance. A common theme I’ve noticed is that a number of people that had personal issues with Drouin because of his quitting on the team during the 2015-16 season or uncertainties about his performance of a whole are generally ok with the trade.