It was discussed so many times, like here, but it seems the answer is always that it was decided like that in the begining.
Still, can it be changed today, to accept questions like this one?
To somewhat split the difference of the other answers, I think it could make a lot of sense to allow questions around home distilling. If someone has a question more generally about distillation, particularly in a commercial setting, I think leaving that to https://alcohol.stackexchange.com/ seems reasonable. But if someone has a question about distilling their fermented products themselves (i.e. at home) I think it could be reasonable to ask here, as long as they aren't specifically asking about how to break laws.
See my argument here for why I personally think merging the two SE sites could also make sense. But I think the same argument applies to Homebrewing just being a little more permissive instead of eschewing questions that, while about the creation (and/or modification) of alcoholic drinks at home, but aren't technically about homebrewing. It seems like they're similar goals and would presumably appeal to many of the same users.
I would have no objections to opening up the site to more distillation questions; as it is a post fermentation step :)
I think these questions should be asked over at https://alcohol.stackexchange.com/ I think there is plenty of expertise on that stack. Let's keep it to homebrewing and wine