Monotone Tan–Zhou dimension conjecture for Lüroth approximation sets

Let $L(\psi)$ be the set of points defined by the Lüroth approximation condition associated with a function $\psi:\mathbb{N}\to(0,1]$, and let $\underline{\tau}_\psi$ denote the corresponding lower approximation exponent. Assume that $\psi$ is non-increasing. Monotone Tan–Zhou conjecture. Then

$$\dim L(\psi)=\frac{1}{1+\underline{\tau}_\psi}.$$

The monotonicity hypothesis is motivated by the paper's counterexamples to the unrestricted statement. Under this hypothesis, the asserted exact Hausdorff-dimension formula remains open in the supplied text.