Sorry, John, but I’ll agree with the thought that if the winemaker did not ‘intend’ for Brett to be there and it does, then to him or her, it would be considered ‘a flaw’. The consumer may not feel the same, and that’s okay . . . but intent does need to be taken into account, no?
On the other hand, should a winemaker choose to bottle his or her wine unfiltered with any potential ‘food’ for brett to consume, then they are setting themselves up for this because they are not able to ‘control’ provenance, storage and shipping during the life of the bottle.
Cheers.