Hi!

So I'm wondering how would "bad wiring" cause a TV to get
destroyed?
I've never heard of this before.

The voltage on the outlet the TV was plugged into could be too low, too high
or fluctuating often and causing stress to the TV's circuitry.

The outlet itself could have been wired improperly, such that it was
carrying a voltage that was totally inappropriate for the TV set. It is
possible to wire a 110 volt outlet (where 110/120 volt power is used) to
have 220/240 volts coming to it. The results from this would be immediate
and probably catastrophic, so if the TV did not fail immediately, this is
probably not the cause.

Finally, as another poster mentioned, there could be a poor neutral
connection somewhere in the wiring. If this were the case, the two "legs" of
110/120 volts AC will not be balanced and the voltage on each one will
fluctuate wildly as loads come and go.

William