We aren't past the era of Star Trek. Deep Space 9 upgraded the franchise for 90's-style Iraqi/terrorist conflict. Voyager removed us from the regular formula all together. Enterprise would have been good if it hadn't of been manhandled. You can, really, do whatever you want with the franchise. Which is why it's constantly revisited by Hollywood.
And, yes, the original series tanked --but not for long. It was back in action, and big enough to inspire serious remake activity, just a few years later. And TNG was hugely popular -- hell, UPN's backbone is built on TNG. DS9 also has a strong following. Voyager was the beginning of the end, ratings wise, but still strong enough to keep the boat afloat. Enterprise's hideous demise was the fault of bad writing and no thought, not the audience getting tired of the series. Enterprise should have been an edgy political thriller with aliens, but that takes talent that Team Star Trek lacked.
All that said -- grave robbing is exactly what this is. As usual -- and Star Trek is the poster child, also, for this problem -- the men behind the curtain don't know what we want. They want to cash in on the franchise, and good for them, but they're so far removed from the fans it's impossible for them to think of a working concept beyond throw every element and character together and write a script in a weekend. Star Trek's always been simple, often mind-numbing, but we've started to see it try to copy itself. Nemesis, for example, was a desperate attempt to recapture Wrath of Kahn. If it's not doing that, it's biting off more than it can chew. Enterprise could have followed the rise of the humans/Starfleet/the Federation and nothing else and been wonderful. Instead we got feel-good scripts, ridiculous love triangles, the "Temporal Cold War," and the most misguided need I've ever seen to feature all the villians from the other shows...even though that meant completely rewriting the Star Trek bible, which, when fans complained loud enough, resulted in equally misguided attempts to try and explain away what they had done.