I'm with the idea of Blazers should change their coach since no positive result happens for 7 years with their current coach. However, even you put Stever Kerr or Coach Pop in the current Blazers team right now, I will bet that they will not be the champion.
What they need to do is to put some strong backup players around the main core. Remove Lillard and CJ on the floor and they are doomed. Blazers are known for not participating in catching big fish or at least have an effort to target a well-good player. They are like that for several seasons wasting the talents of Damian Lillard. Fortunately for them, Lillard already committed that he will not leave the team and will remain loyal. He said that, if I'm not mistaken 2 to 3 years ago.
Coach is a big factor, no doubt about that. The presence of coaches like Steve Kerr or Coach Pop will boost players morale.
But in today's NBA, morale is not enough. Blazers should overhaul first their lineup and just consider changing coach later on.