There should be a name for the fallacy of drawing a specific, practical conclusion from an abstract or metaphysical premise. "Vitalism is false, therefore Soylent is a good idea" is such a fallacious argument. Clearly, the premise doesn't follow from the conclusion at all.
What follows from vitalism being false is that something like Soylent, that is, an entirely synthesized meal replacement, isn't metaphysically impossible. But I haven't seen anyone making metaphysical objections to Soylent; all the objections I've seen have been practical: nutrition is a much, much more complicated field than the makers of and advocates for Soylent seem prepared to accept.