There is some validity to your proposed move, but here is the comparison I would make: the Titanic needed more lifeboats, not better deck chairs. Obviously it's not a perfect comparison, and there's a lot of hyperbole in that statement, but the crux of it is valid.
The Blues need more RHS's in the top 9, RW's and C's especially. The Blues have bigger issues than upgrading LW, a position of relative strength. Judging from your other posts, I think you get where Blues fans are coming from here, so I don't want to beat a dead horse any more than we already have.
FWIW, I think you're dead on here. My read of the situation is that PD wanted Fabbri + Thomas/Kyrou (maybe an additional small +) at the TDL and DA offered Fabbri + 1st (in this case Winnipeg's first). Both sides stuck to their guns and deal didn't get done then.
Nothing to back this up, just my opinion, but looking at the other rumored deals at the TDL - specifically around Karlsson/Ryan - I think that PD might've just not had the time/resources to devote to a deal around Hoffman. Obviously the offseason allows a LOT more time for negotiation so who knows?