If you remove the thermostat and redline it in a garage it still won’t be able to keep up because it doesn’t have the airflow that’s required

The concept of closed loop cooling for servers has always existed and it works for home computers. What is conventionally called closed loop cooling just means that you transfer heat from the computer to a liquid and then from the liquid to air. Transferring 100MW of heat to the air is what makes this difficulty especially in a stationary computer.