Starfleet already knows he is from the future.
We don't know what Starfleet knows.
The only one whose coming across as desperate is you. You keep serving it up and it keeps getting smashed back in your face. Then you try to spin it as people being inflexible because they don't share your views.
The universe suffered a wound with the loss of Vulcan and it will heal on its own terms. It doesn't need Spock running around trying protect every person from every tragedy that is about to transpire.