Separating and then reconstituting the wine is the part I would personally draw the line at. Maybe it's fine. Maybe they're grossly altering the wine in a way that negates e.g. health benefits, and it's not "wine" in the sense that consumers understand it to be.
More generally, I think people are just tired of producers fucking around with their food in various ways.
This isn’t a big deal. You should probably be more concerned about the pesticides. These machines do dealcoholization, remove volatile acidity (vinegar), alter acidity (done with ion exchange, as opposed to adding tartaric acid directly to the wine). Yeah, there are probably some negative side effects as a result of these techniques, but I'd bet big that they are vast improvements over the alternatives and that the negative effects are dwarfed by those of pesticides
More generally, I think people are just tired of producers fucking around with their food in various ways.