The linchpin of this tactical situation in the Red Sea is the presence of the Iranian spy ship MV Behshad (the one that replaced the Saviz). It is giving precise targeting information of commercial ships to the Houthis to launch land-based missiles and drones. Without this ship, the Houthis would be shooting wildly into the ocean with the granularity of open-source maritime surveillance networks like marinetraffic.com.

Behshad's transponder's last update: https://www.marinetraffic.com/en/ais/details/ships/shipid:65...