So I just completed the main scenario and moved on to the Arks.
Got everything setup and the game tells me to research and build the beacon as usual, so I set up a couple of workshops. I see nothing in the tech tree, so all I can do is research the next tier. Perhaps something pops up later.

But nothing happens, so I research the second tier. Still nothing.

So... Is this a glitch?

Yes, that's a glitch. Most techs are available to me when I play Arks, so this is something unusual that's happening in your game.

There are a few techs you can't research in the Arks scenario (hunting is unavailable in this scenario and the factory must be earned through scouting missions) but the vast majority are still available.