My personal take on the Kelvin Universe.
Yes, the casting was amazing (RIP Anton Yelchin .... ).
But when the first Kelvin movie came out, the franchise ... Star Trek ... it was pretty moribund. The first movie is Abrams at his best. LENS FLARES. ACTION. LENS FLARES. COMEDY. LENS FLARES. FAN SERVICE. LENS FLARES.
It's like getting on a superfast roller coaster ride while eating a bunch of cotton candy and having nostalgic scenes of Star Trek shown to you (but with LENS FLARES). You have a great time, you're happy, and at the end of the ride you're glad you did it ... so long as you don't think about it too much, and ignore the terrible pain in your stomach from all those empty calories.
By the second movie (Into Darkness) those tricks- the remixed nostalgia, the LENS FLARES, and the action/comedy/sugar rush have worn off, and you realize that it's just empty.
Such is life with Abrams. He can reboot a franchise, but he can't keep it going. He understands the symbols, but not what they mean.
The third movie is the tragedy. Because while it's not a perfect movie, it was a really good Star Trek movie. It's a shame we didn't get to see that crew again.