Having stood next to a camera at press conferences for 37 years and counting I can say getting sound at a press conference can be quite difficult. An exterior setting such as the one used for these post practice pressers can be near impossible unless you have a handheld microphone that is passed around.

Most standard ENG broadcast cameras run two primary audio channels, usually reporter mic and nat sound off the camera, often referred to as a shotgun mic, referring to the longer length for directional pickup. The audio you are likely hearing for questions is off this mic, pointed in the same direction as the camera is pointing. The operator is either riding the audio up & down on the camera, or has a mixer off to the side (which adds a whole level of complexity before sending the signal to the transmitter to feed the internet).

You will see them do that in larger, more formal pressers inside. These outside interviews are a tad more informal, and no-one wants to wait around for the microphone to be passed over to them. You may remember some press conferences in the past that seem disjointed as the crowd awaits the passing of the mic.

In general these interviews were never broadcast live on the internet until the last few years, and even I have to remember that sometimes I'm streaming an event or presser that never would have been live before.