I have made dessert wine, in Canada we usually do icewine where we freeze the grapes, leaving the water behind and pressing out the sugar. Botryis effected wines have the noble rot dehyrate the water out the grapes, concentrating the sugar. I find sometimes I can taste the mould in them...
In most wine making, botrytis is like cannibis. No good.
here;s some BA grape bunches lol
https://fthmb.tqn.com/q5q7LSRc1u-q56FimgoVP3p1Tdo=/2272x1704/filters:fill(auto,1)/botrytisclusters-56aa13b25f9b58b7d000bfd9.jpg