No air recycle mode on defog/defrost setting?

My 2021 will not allow me to use the air recycle mode when the HVAC selector is set to defog/defrost. Is this normal? I seem to recall this was allowed in my 2011 4runner.

 

My 2021 is the same way. IIRC all of my Toyotas have been that way except maybe the ‘89.

 

I thought it automatically uses recycle just doesn't let you select the button ~ like an override setting.

 

You can’t select recirculate in defrost on any modern vehicle.

 

Google:

On damp, rainy days there's probably enough moisture permeating the interior fabrics, the occupants' clothes and the carpets to keep the humidity in the car near 100 percent for a long time. But cool, fresh air, even at 100 percent relative humidity outside the car, will have far less relative humidity when it's heated up in the heater core and then cooled off in the a/c evaporator. Yes, the recirc air goes through the same heating, cooling and moisture-removal process in the heater, but it picks up plenty of moisture inside the car before it gets sucked back in for another round. That's why some cars automatically use fresh air in Defrost mode, giving you no choice.