Effects rippling both back and forward through the timeline. Not the way I'd have liked it (I want Data's head under San Francisco with all his memories up until TNG season 5!) but it's official now. And it frees them from any continuity issues with the old shows as well as the new series.
It does say (insofar as I can make it out with words missing) that a lot of stuff is still the same in both. The retroactive-change idea is just meant to open the door for
some things to be different, or to justify the things that already seem to be different (e.g. the
Kelvin's huge size, Pike being about a decade too old, Earth's cities being so much more built up). The general idea seems to be that
most of the pre-2233 history is the same, but that certain details don't align.
The way I might have explained it was that--in the final black hole-like opening, Narada was torn to pieces--and those made it to different places in the timeline--explaining the similar looking Romulan drone from ENTERPRISE, the NX-01 era tech looking more advanced than Daedalus only TOS history. That and the time travel story from Voyager lead to to the Kelvin Timeline--with ships looking more advanced.
No.
Enterprise was always, always meant to lead into the
same history as TOS, TNG, and the rest. It was a prequel. It was never meant to branch off into an alternate history. (This was confirmed by "These Are the Voyages...," despite all the other things wrong with that finale.) The differences in the appearance of the technology are merely differences in the real-world technological sophistication of the respective productions. Roddenberry didn't want Starfleet technology to literally look like it was made with 1960s resources; that was just the closest he and his staff could come to approximating future tech on their budget. Which is why they completely redesigned the look of the entire universe once TMP came along, and why Roddenberry asked fans to pretend that the Klingons had always had ridges and TOS just hadn't portrayed them accurately.
Besides, aside from superficial aesthetics, I don't agree that ENT tech
did look more advanced than TOS tech. NX-01's consoles had cooling fans, while NCC-1701's consoles were advanced enough not to need them. NX-01 had handholds all over the bridge and the corridors in case the gravity went out, while NCC-1701 was advanced enough not to need them. TOS tech looked more minimalist, more exotic, less practical, and all of that makes it look farther removed from today's technology. And then there are obvious things like the lack of computer voice interfaces, the less reliable transporters, the lack of deflector shields and tractor beams, etc. As long as you can distinguish between the advancement of the in-universe technology and the advancement of the real-world production techniques used to simulate it, I think it's clear that NX-01's tech is distinctly less advanced.