If Sony reaps brand benefits from naming a "partially owned company" "Sony xxx", then Sony should also suffer when one part of the whole does something damaging to the brand.
Can't have it both ways.
Your clued up person may know the difference, but the average person is not that clued up.
While Sony certainly stood to reap the brand benefits, they also reaped almost all of the negative publicity.
That sounds like someone failed in their due diligence role, rather than any reason I should pity Sony.
Mainly, though, this corporation, which began with Sony and ended with Sony, fit very well with the Sony culture of abusing consumer trust for additional profit.