The Archons were essentially irrelevant to the episode.
They were supposedly the reason the Enterprise was there but Kirk didn't seem that concerned about them.
It was not like on other planets where Kirk had to fix some problem created by the firstcomers.
If the episode were called Red Hour then the Archons need not have been mentioned at all.
I was waiting for some great reveal about the Archons but got nothing.
Captain's Log. Stardate 3156.2. While orbiting planet Beta Three trying to find some trace of the starship Archon that disappeared here a hundred years ago,...
Kirk's not too concerned about the crew of the Archon, because they would all be dead of old age. He's investigating what happened to the ship at this point. Shortly, he learns exactly what happened to the Archon:
SCOTT: Captain, we're under attack. There are heat beams of some kind coming up from the planet surface.
KIRK [OC]: Status report.
SCOTT: Our shields are holding, but they're taking all our power.
SCOTT [OC]: If we try to warp out or move on impulse, we'll lose our shields and burn up like a cinder.
KIRK: Orbit condition.
SCOTT: Checking. We're going down, Captain. Unless we can get those beams off us so we can use our engines, we're due to hit atmosphere in less than twelve hours.
KIRK: Keep your shield up. Do everything you can to maintain orbit. We'll try and locate the source of the beam and stop it here.
Now his number one mission is to stop the attack with heat beams on his ship. Since the powerful Enterprise is losing the battle, the Archon being 100 years older technology (similar to ENT?), succumbed to the heat beams and fell into the planet.

Both starships entered orbit in peace, and the Landru machine's first action is to destroy the ships to prevent any interference with his rule. As for the Archon issue, Kirk repeatedly told Landru that he was the Archons, essentially back for revenge. I guess that was the best reveal on the Archon theme we get? Thankfully, Kirk talks Landru into suicide to first save his ship, and secondarily, to free the world from the 6000 year computer rule.
I agree, the title is so-so, but the episode had its good moments like Kirk's first computer kill.
