Right ,
I do understand all that.

I can see the thermistor that measures the air temperature.

In this case I presume that the "hot wire" is not a "hot wire", but a hot film - the shiny plate inside the flow-thru passage (They probably went to this hot film design so that water droplets and solids would not impact the hot wire - they just flow on past it.)

My question still is - What is the purpose of the dead-end cavity with 2 vertical wires near the bottom of the sensor - see picture??