https://wccftech.com/soli-gestures-pixel-4-few-countries/

One by one, Google started teasing the features of its upcoming Pixel 4, with one of them being Soli gestures. Without physically interacting with the Pixel 4’s display, users can employ hand gestures to carry out specific tasks, all thanks to a bevy of sensors housed at the upper portion of the upcoming smartphones’ display. However, carrying out these tasks is going to be limited for a lot of people and it will all depend on where you reside. Thanks to small details shared by Best Buy, which have now been altered, Soli gestures will only be available in a few markets.

According to the details present on the Best Buy landing page (spotted by XDA Developers first), it talks about the availability of Soli gestures for the Pixel 4: