Standalone 5K monitors are currently unavailable via Apple in various countries. 9to5 Mac noticed this and offered some explanations why.

We have verified Apple’s website from different countries, including the United States, Canada, the United Kingdom, and Brazil, and in all of these, the LG UltraFine 5K Display is not available. Apple doesn’t clarify whether the unavailability is temporary due to a new model arriving or supply constraints. The same thing happened last year, with LG UltraFine 5K disappearing from Apple Stores in May. Two months later, LG announced a new generation of the monitor — which is the model that was being sold until now. Now with Pro Display XDR, Apple could simply remove the LG monitor from its stores. But since the LG UltraFine 5K Display is still listed in the Apple Online Store, that’s less likely. However, it’s hard to imagine that Apple will continue to work with LG to launch a new monitor.