Grigoriev–Koshevoy's exponential lower-bound conjecture for skew-Schur polynomials

Let $s_{\lambda/\mu}(x_1,\ldots,x_n)$ be the skew-Schur polynomial, where $\lambda/\mu$ is a skew shape, and let $\operatorname{Trop}(s_{\lambda/\mu})$ denote its tropicalization. The tropical semiring complexity of a tropical polynomial is the smallest number of gates in an arithmetic circuit over $({\mathbb R},\oplus,\odot)$ that computes it using the tropical semiring axioms.

Grigoriev–Koshevoy's conjecture. The tropical semiring complexity of $\operatorname{Trop}(s_{\lambda/\mu})$ is at least exponential.

This concerns the circuit complexity of tropicalizations of skew-Schur polynomials. The supplied source attributes the statement to Section 5 of Grigoriev and Koshevoy, but gives no resolution evidence; its status is therefore open.