This joins a growing list of other anomalies in the standard model, such as muon g-factor, neutron lifetime, and W boson mass. The problem is that these anomalies don't seem very useful for actually building new theories, since they involve complicated interactions of beyond-the-standard-model physics in the 10th decimal place. Contrast with a collider experiment, where there is a very clear signal of which new particles exist.

It's the difference between a number being wrong, and seeing an entirely new phenomenon which we didn't expect. To move beyond the standard model, we may need experiments that can give us the latter.