The valley moves inward and deepens with age, as predicted, but neither shift is significant at current sample size.
The radius valley is not a steady-state feature of atmospheric stripping but a fossil of when photoevaporation happened relative to disk dispersal, so its position and depth should change with stellar age.
Unresolved
We queried the NASA Exoplanet Archive for planets with a measured radius, orbital period and stellar age, and kept 0.5–4 Earth radii and periods under 100 days. That gives 2,713 planets. We estimated the radius distribution in four age bins with a Gaussian kernel, located the minimum between the super-Earth and sub-Neptune peaks, and bootstrapped both the valley radius and its depth. The comparison of interest is stars younger than 1 Gyr against stars older than 5 Gyr.
This is the one result in the set that is neither a pass nor a failure. The distinctive prediction — age dependence — is visible in the point estimates, but the confidence intervals are wide enough to contain no effect. Calling it support would overstate the data; calling it a refutation would overstate the test. It is a question that a larger homogeneous age sample, or a cluster-based comparison, could decide.
Stellar ages are compiled from heterogeneous methods and are often uncertain by a factor of two; that error alone can wash out a 0.3 R⊕ shift. The sample mixes transit and radial-velocity discoveries with different radius completeness. The valley location depends on the kernel bandwidth and on how the two peaks are identified, which is why we bootstrapped the whole procedure rather than the bin means.