Well, the incentive of course is if the GOP smell obstructionism without purpose, they kill the filibuster, appoint Gorsuch anyway. If (a) nobody else on the court leaves/dies in the next 3 years, and (b) the Dems win the 2020, and © the Senate flips Dem, that’s a huge win for the Dems.
The chances of the first happening are around 20–25%. The chances of the second happening are 43%. The chances of the third happening approach nil.
That’s not a trifecta I’d bet on.