It's about how the Trek of today is unrecognisable as Trek, on a fundamental level.
How so is always my question? Star Trek is, by design, a large sandbox to operate in. It tells dark stories, as well as lighter ones. The biggest thing when people say Star Trek is "unrecognizable" is that it doesn't look like TNG era. Fair enough if that's what you grew up with as Trek. I had TOS as Trek and the first episode I watched involved Kirk shooting his best friend, and the second ended on the note of a bride mourning the death of her groom all alone. The idea that Trek is always a shinning light of optimism is woefully simplistic understanding of Trek's own history. Especially when the top rated films and episodes involve incredibly dark themes, like Best of Both Worlds.
Yes, TNG was maligned as "not Trek" because it was, to use your terms, unrecognizable as Star Trek. That's what Star Trek does. It gets updated, it changes, and it, like any other pop culture franchise, has hallmarks of the time it is created in. That doesn't make it less Star Trek. That just makes it not for every single person who is a Star Trek fan. Just like TNG was not for everyone, TMP is not for everyone, etc.
What is new is the ability to showcase the knee-jerk reactionism online immediately to air out grievances and claiming the ruination of all Trek, and how we will never forgive them for perceived slights and insults by production teams who dare to present their own take rather than conforming to past iterations. What is strange is this franchise's supposed claims around an optimistic future when there is a strong desire to keep Trek locked in the past, never changing its look or approach to comfort nostalgic feelings. It's confusing as I'll get out that Star Trek is both about the future yet must adhere to it's past at every turn.
All of which is wielded as a weapon against people who have a shared common interest in this franchise, yet insult each other at the barest slight. As Spock would say, fascinating.
