Well, I say it's not Star Trek because (to me anyway) the thing that made Star Trek distinctive is that it didn't say "it's science fiction, so anything goes". Especially for a '60's tv show, that was a pretty radical stance to take. It set out to establish some hard-science ground rules, and even though it also made up some of its theoretical technology, it mostly kept to the rules it laid out.
And one of the earliest and non-negotiable rules was the Enterprise is not meant to function in atmosphere. That's why it had such a bizarro shape. That's why it had shuttlecraft that were aerodynamic.
That alone made Star Trek stand out when it first debuted - they dared to have a "spaceship" that didn't look like a Buck Rogers rocket. Even that minimal amount of understanding of what space travel truly might be like set Star Trek apart from any tv show that came before it (and a lot of them since).
This new thingamawhizzy with the Star Trek label starts out with the Enterprise not just blithely tootling about in atmosphere, but going underwater. This is the filmic equivalent of giving a five-year-old an Enterprise toy and him taking it into the bath with him. Sure, it's fun but it's ridiculous.
It does answer one question I had from the first movie - if they assembled the Enterprise on Earth, how the heck did it get into space? I thought maybe there was some clever rationalization for that, but now we know the answer - JJ and company think that's how the Enterprise works.
That's how the movie starts, by the end they're actually ignoring the rules of freakin' gravity in order to justify another kickass action sequence.
It's actually an entertaining movie in that a lot of exciting stuff happens, but it really is like a five-year-old in a bathtub full of Trek action figures without any understanding of anything, including basic physics. I found it ultimately insulting, just as I do any movie that expects me to swallow a pound of dumb for an ounce of action. It's just a little extra sad that this particular dumb movie has a Star Trek label on it.