As I look at the Fournier deal, assuming that 4 years / $78M , starting at about $18M, are the correct parameters, this is not a horrible deal for Fournier on the Knicks but it makes a lot less sense for the Celtics to pay this for him. We have Brown and Tatum plus also Richardson, Langford and Nesmith. Fournier is a lot like these players in terms of position and role at least to the extent that he needs to score to help the team. Brown and Tatum already give us a lot of what Fournier can give. It is nice to have more of it but we don't need it as much. It is a better fit the Knicks. I have no disappointment over this. Based on what I saw of him on the Celtics, I think he is a tick over-rated anyway but $18M and up is not a horrible contract either for the Knicks, just not good a fit for the Celtics.
As to how this compares to Smart, again, assuming 4 years / $68M is what it is, I would rather have Smart at that number on this team. Although he may not be a 100% natural PG, he can play PG just fine for us in my opinion, something Fournier can't do. We can lose Fournier and it really doesn't create a hole. Richardson, Langford, and Nesmith can all do what he does to varying degrees as the depth behind Tatum and Brown. No one else on the team can do what Smart does. Now if we get Schroder, then sure, Smart becomes much more expendable.
I don't think either the Fournier contract or the Smart contract will prove to be "immovable". They are both good fits for the respective teams in the short term and if the roster composition needs to change over time, either player would be a reasonable trade asset. I see this has become a big debate but it all just kind of makes sense to me. Fournier is just a far better match for the Knicks than for the Celtics.