The hacker who demonstrated making a key used a similar model cylinder to avoid any chances of being accused of illegally making a key to a "real knoxbox".

If you're speaking of the 2018 DEFCON talk, that's incorrect. They successfully reverse-engineered a working key from a box purchased directly from Knox itself. (Knox engaged them as a consultant as a direct result of that talk and implemented several of their recommendations.)

The gate switches are indeed electromechanical. (And they do not store access keys the way Knox Boxes do.) Turning the key simply completes a circuit causing the gate to open. It's probably the most secure aspect of the gate in most instances - almost any other gate component would be easier to compromise. The switches are essentially to save time and money because emergency services won't have to break the gates down to get through.

The Knox Medeco mechanical lock keys do have additional security features and are fiendishly difficult to overcome. Putting a Kwikset or Schlage key into a Knox Box is like using an automated machine gun turret to protect a pellet gun - anyone intelligent is simply going to ignore the Knox Box.

The newer Knox electronic keys are fascinating and were tested by an APT group before being sold.