He was definitely wearing a wire... for sound. It's a mic. Trump has one too. Either hidden in his tie, lapel or taped to his chest. This was a live broadcast. Of course they're wired for sound.
This is not the hill to die on guys.
This is a lav mic. It's most likely a tertiary back-up (worst case scenario) if the podium mic and the mics they definitely both have hidden in their neck ties fail. I'm sure if both were to lift up their coats and turn around you'd see a few wireless transmitter packs on them. This mic is there as a back up to the back up. IF the shit hit the fan, audio wise, this would at least transmit something while the audio team scrambled to fix the issue,
Appears to be a Sanken COS11 with a pretty common clip with adhesive around it that was probably taped further up his wrist initially before it fell.
Also, for the record, they were both 100% for sure "wired". On live broadcast no sound mixer would trust 1 microphone on talent. That would be suicide. You'd have multiple failsafes and each person on that broadcast would certainly be wired for sound.
Source: Film and television sound mixer for 15 years.
They're all wearing MULTIPLE mics. Imagine you are hired as the sound team for a Presidential debate being broadcast on live television. Are you just going to throw a mic on the podium and call it a day!? You are going to have redundancies for your redundancies. Because if the shit hits the fan you need options until you can troubleshoot the hero mic.
Half of the time the mic on the podium is just there for looks. Talent will be wired with at least 1 if not more hidden lavalier solutions and wireless transmitters sending back to the sound mixer. If one goes down it's seamless transition to a backup mic until a solution can be found. If that backup goes out you possibly have a tertiary mic. If that goes down you just leave and become a real estate agent or something.