Strict monotonicity conjecture for Mori flips

Let $g\colon X\dashrightarrow X^+$ be a birational morphism between $[200~\mathbb{Q}$-Gorenstein varieties, together with birational morphisms $f\colon X\to Z$ and $f^+\colon X^+\to Z$, such that $g$ is an isomorphism in codimension one, $-K_X$ is $f$-ample, and $K_{X^+}$ is $f^+$-ample; such a transformation is called a Mori flip. Strict monotonicity conjecture.

$$e^{\rm str}_{\rm alg}(X)>e^{\rm str}_{\rm alg}(X^+).$$

This is the flip case of the proposed strict monotonicity of the algebraic stringy Euler number under elementary birational transformations in the Mori program; the source does not state whether it has been resolved.