In the US, it's open for unlicensed use for very low power devices. That is, it's open for WiFi. It's used by WiFi 6E, 7, and 8.

https://www.fcc.gov/document/fcc-opens-entire-6-ghz-band-ver...

Perhaps not for much longer:

https://news.ycombinator.com/item?id=45785987

The Trump administration is diligently working to undo that. Why dedicate such a resource to the public, when you can let private companies charge us to use it?

https://publicknowledge.org/ted-cruz-wants-to-sell-your-wi-f...

They're also planning some overlap.

https://www.ofcom.org.uk/spectrum/innovative-use-of-spectrum...

China has already reserved the entire 6GHz for cellular and vehicles.