It's relevant because ground based satellites add observational capacity. If a ground based telescope can't get a good view, that's when you queue up Chandra or James Webb (Hubble is not the same type of telescope, and it's workload is not interchangeable).

Astronomers have thousands of interesting things they would like to point their telescopes at. There are thousands of capable ground stations that could take the easy targets, and only 2 x-ray satellites which should be used only for the highest value targets where absolute clarity and resolution is required. But if you start obstructing those ground stations, the workload must be taken over by just 2 satellites.

Ground stations are valued because they help solve the capacity planning problem. More usable telescopes === more observation time. Having more ground stations frees up the 2 satellite telescopes for truly stunning shots.