Tie that chip to a beamformer (silicon labs have a few) and you have a phased array radar, which is a radar that does not move at all (pretty cool in my opinion)

Also, 15usd is not cheap for this kind of chip. You can buy a full wifi 7 rf/modem or a 4 core arm64 soc with this kind of money.

You can't use an external beamformer with this chip; it has the antenna built into the package itself. The chip doesn't have pins for RF input/output to bypass the built-in antenna.

60GHz radar is very different from WiFi. 15USD actually seems about right for the functionality this chip offers.