I mean isn't space X testing satellites with sat to sat lasers?

In that case you don't need to ground lasers, you just beam the data where you have unjammed communications with the cost of higher latency.

More than testing. That is their primary on-orbit link method for Starlink satellites as of 2.5 years ago: https://www.pcmag.com/news/starlinks-laser-system-is-beaming...

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