In Alchemy Premier Draft limited, I surveiled a land to the top with the on-tap trigger of Starfighter Pilot. Later that turn, I attacked with Hydroponics Architect and its trigger to give a random land a draw trigger successfully resolved. However, the land on top of my library remained revealed with no extra ability.

This is incorrect in one of two ways. One option, the game is still displaying the actual card on top and letting me know whether or not it was randomly chosen with Hydroponics Architect. The second option is that it kept the card as it was revealed whether or not it was given the ability (and by random chance, it didn't have it), giving false information. In this situation, the Hydroponics trigger should "un-reveal" the top card of the library if it was a land that could be affected by its trigger.