Year 5000 minus 3188 (the year which Disco S3 is in) would mean 1812 years after Discovery Season 3 (possibly 2000 years) - unless I'm miscalculating?
UFP should have still been a Type II civilization (all major species of UFP having Dyson Swarms around their native stars) ever since it was created (since it was possible for us to start construction of a Dyson Swarm in real life since 1990), on its way to becoming Type III (making more Dyson Swarms around new member species planets over time)... and fully realized Type III civilization on its way to becoming type IV by the 32nd century (aka, Milky Way stars would have been fully harvested, along with Andromeda, and all the adjoining dwarf galaxies - the overall radius of stars that UFP have harvested using Dyson Swarms or Dyson Spheres would probably have to extend some distance beyond Andromeda when you take into account full scale automation and that Slipstream v2 allows for 10 000 Ly's per minute in late 24th century already).
TW beaming would make this ridiculously easy... just use 2 previous Dyson Swarms to materialize 1 new Swarm around a distant star immediately using the star's power (which would be absolutely massive).
Given how Trek writers seem utterly oblivious to Type II, III and IV civilization designations and their capabilities (especially when merged with the technology UFP has), having UFP reach Q level status by the year 5000 seems... ok I guess.
Which book was that in again?
I realize you're a big proponent of Kardashev stuff, but I am of the belief that there are forces (Q or perhaps less than Q) that are actively keeping down the technology level of the Galactic Culture(s) at large. It could just be pseudo-natural, a result of resistance to AI, as AI tends to become evil fairly often (as seen multiple times in TOS and very, very recently in Discovery), with groups opposed to technological advancement in certain fields kneecapping advancement in others.
There's also the fact that humans, per Lower Decks but implied in other shows, have the ability already to ascend to a higher plane of existence by pure mental discipline I guess. Admittedly, I presume the individual in Lower Decks was actually preyed upon by a being on these higher planes, but the concept still seems readily available, especially if we take TNG's Transfigurations (and a similar-level culture with ascending beings) into account. This implies that the Human-Zalkonian-Galactic culture of the late 24th century is almost near its end, perhaps a few centuries shy of achieving some sort of "evolution" beyond physical existence (but done via some sort of mental clarity and not further technological progress).
We don't see many more, super-advanced cultures than Humanity, who are pretty much the infants of the Galaxy, but this is par for the course. Once they fully enter the Galactic Stage (and I'm talking the Alpha-Beta Quadrant corridor where 9 out of 10 series takes place) all technology is evenly exchanged and about equal. Like the "stone age" Native Americans who quickly adapted to guns and horses when the time came (the ones who survived. Oy). The ones we see, primarily in TOS mind you, are remnants. Survivors of long lost civilizations following some sort of catastrophe or event. I've hypothesized in the Picard forum that this was AI taking down most of these civ's that were too large for their liking, but this could be the non-corporeal beings at large, or just one all-powerful one, or maybe there's no difference. Perhaps the Q are an ancient Q(uery) system written by some bored programmer in the long, long ago that moved on from there. At what point does "artificial" intelligence and "natural" intelligence become meaningless distinctions? Does the Q(uery system) and the Organi(c processing simul)ans laugh at the civil right bickering of these funny little microbrains?
But to circle back to the ascendancy of humanity in Lower Decks and Transfigurations... what is going on here? Is there some way to interact with the realms of the non-corporeals inherent in humanoid biology? Or are the non-corporeals/AIs helping them achieve this, perhaps underhandedly? Did that Koala eat that guy? (Yes) We don't have all the answers, but that's kinda the point.
Humanity (or, rather, Galactic Society) not advancing much from the 2160s to the 3180s seems about right on the assumption that technology and culture has hit an artificial plateau, probably centuries or millennia beforehand, and these incremental advancements occasionally seen in other episodes are not as accurate or galactic rearranging as they should be. Once someone, somewhere in the galaxy or a nearby one (or anywhere, really), discovers, creates, or advances just one teensy bit beyond a specific threshold, things are due to cascade in the Federation (or whoever)'s favor and Q-dom will be a short distance away. Year 5000, sure. 4000, no worries there. 3200... maybe?
I haven't addressed the other Elephant in the room: Time travel. Humanity, er... uh..., Galactic Society has mastered the art of temporal manipulation, and the Star Trek franchise seems to show us this progression firsthand. The Vulcans didn't think such a thing could be done in the 2150s, but they surely can't say that in the 2380s, where it was suddenly becoming a very common occurrence on even run-of-the-mill starships. The escalation of time travel might be that Singularity push that cascades everyone into Q form, but this is likely stopped and controlled by the upstreamers... the beings (for good or worse) controlling and manipulating events from the TCW (2700 to 3100, at least), which we see actively being done in Enterprise, and similar events in "Captain's Holiday" and "A Matter of Time". The events of Discovery are now beyond that (supposedly), beyond the point where we can say that the Galactic Society may have been kneecapping itself purely to kneecap its enemies. What will happen now? Will Q come and accept them with open arms in their heavenly kingdom? Or will the Koalas get there first?
