Countless companies and industries enjoy making up scary stories when it comes to justifying their opposition to making it easier to repair your own tech. Apple claims that empowering consumers and bolstering independent repair shops will turn states into “hacker meccas.” The car industry insists that making it easier and cheaper to repair modern cars will be a boon to sexual predators.
That’s pretty shitty. They’re probably talking internally about the fuse as if it’s some type of tamper seal. But fuses blow sometimes, they’re literally sacrificial. So somebody has told their support techs that anyone with that fuse blown has tampered with their battery and they’re just repeating that line to customers (some guilt of tampering, some innocent).
Or maybe you just got unlucky with a dumb support tech. If that’s widespread, they deserve to get sued.
Apparently some earlier models of their batteries had a user accessible hatch to change fuses, so I’m inclined to think they intentionally moved from a repairable to non-repairable model.