From an engineering perspective, there's probably a lot of resentment that Vulcan's invented everything useful and continue to break new grounds in new fields, leaving nothing for humans to do but be lonely little technicians toiling off on the periphery where Vulcans can't lower themselves to go.
Tuvix has all that Ocampan DNA in him right?
Which means that he has the potential to turn into a Starship flinging ascended being just like Kes in the Gift after having his brain supercharged form conversation with 8472 opening up new telepathic potentials.
1. Kes is a child, who translated the nuances of the conversation with 8472 so poorly that she couldn't tell the difference between friend and foe. Tuvix probably wouldn't have been confused, then easily talked his way into an Aliance with 8472 to destroy the Borg.
2. As a space god who can throw Voyager 10 k light years without any structural damage to the ship, just like Kes... Tuvix, who I might remind you is Captain Tuvix, might have waited around caught a second wind, even if it took him a month, and then kept throwing Voyager across the GALAXY until it hit Earth space.