I often have heard ENT referred to as a prequel to the reboot movies. Now, obviously there's the Archer references, which I loved, but I'd think the ENT of the reboot universe wouldn't technically be exactly the same as the ENT tv series, if for no other reason than the Borg episode being a prequel/sequel to Next Contact. Or would the same events have unfolded in the reboot universe too? I do think at the very least, the characters and events of ENT would be very similar in both universes, but are they exactly the same?
According to the Powers That Be and the novel
DTI: Watching the Clock, the timelines were one at the same until Nero appeared in 2233. TOS is "what if the Kelvin got to Earth without incident" and ST'09 is "what if a gigantic deathship appeared from the future?" stuff like the Temporal Cold War happened in both timelines, but the changes made to history are what led
to the universe of TOS (and nuTrek from 2233 onwards), not away from it. Episodes like "Azati Prime" show how large the Delphic Expanse grows post-ENT (it fills the entire quadrant), and since it's never seen nor mentioned in TOS/TNG/DS9 we know the reason is because the Enterprise crew destroyed it in "Zero Hour"
Look at Admiral Marcus' desk in the scene where Kirk and Spock are given their mission to Kronos - there are models of the Aries IV (VOY: "One Small Step"), the Phoenix (ST: FC), the Enterprise XCV-330 (ST: TMP and background art in ENT) NX-alpha (ENT: "First Flight"), the Enterprise NX-01. All direct references to prior events in the Trek 'verse.
Is there any other evidence for or against ENT being a true prequel to the reboot movies?
"In a Mirror, Darkly" directly links ENT with TOS: "The Tholian Web" and "These Are the Voyages" directly links ENT to TNG: "The Pegasus". I think those are pretty irrefutable evidence that ENT is the same history as TOS, TNG, DS9 and Voyager. Don't get me wrong, there are continuity errors but no more so than between the other series' (biggest IMO being how the TOS/movie Enterprise effortlessly zipped around the galaxy when for Voyager crossing it was a lifelong journey)
The reboot movies have gone to great lengths to explain how events stem from Nero's arrival - be it Khan being found and woken early after Vulcan was destroyed, Section 31 building a massive facility beneath the USS Kelvin Memorial Archive, or even why Kirk didn't join Starfleet until his 20's.
As for ENT-new movie links, I love how the "Borderland"/"Cold Station 12"/"The Augments" Augment trilogy works just as well as a prequel to
Star Trek Into Darkness as it does for "Space Seed"/
Wrath of Khan. The effortless Klingon-whupping and Soong's comment about how easily Henry Archer's illness could have been cured (much like the little girl is) work as excellent foreshadowings to events in
Into Darkness.