That’s part of it, and certainly it’s why the Canucks ended up signing him when they did (I.e., the trade market wasn’t good) but the bigger impetus for when that contract was signed is that Miller and his agent, smartly, new they had to capitalize on Miller’s outlier season which was probably unrepeatable so the best case scenario for them was signing before this year. This is why they gave the Canucks an ultimatum in that they said Miller wouldn’t discuss signing once the season started which pressured the Canucks to sign him before the season started. This was a good gamble by Miller as it appears management was never seriously willing to trade him so they caved and signed Miller when his value was the highest.
Ironically, of course, the Canucks took the opposite bargaining position with Horvat which had absolutely destroyed their ability to sign him. Although admittedly, it’s hard to blame management on this since Horvat’s play has been entirely unpredictable.