The planetary body dubbed 'Holoworld', is the remnant of a simulation / training facility belonging to a long extinct civilization. Though approximately 93% of the world's systems are either failed or failing, what remains is still capable of fulfilling it's design purpose within some constraints. A VI interface exists for visitors to liaise with and organize their desired experience.
Owing to extreme data corruption and degradation over time, little is known of the world's architects; save that their existence may have corresponded with the peak of the Iconian Empire circa 200,000 years ago. The Holoworld VI has informed Starfleet that it's architect's civilization fell in what was referred to as the 'Dark Ages' following the fall of the Iconian Empire.