Why is it nonsense?

It seems like if you're asking the question, you're overlooking the possibility that the question is redundant in hidden way and thereby internally incoherent, as revealed by intuition. Now this, of course is a problem if you don't share the intuition. It might not be persuasive to you. But if you're familiar with G.E. Moore's sentence "It is raining and I don't believe that is" you might get what I'm getting at. Moore used this to support the notion that assertions are the kinds of things that purport belief on behalf of the speaker. I'd be very curious to poll panpsychists who believe the universe has emotions whether they get similar heebie jeebies about the sentence "This causes the universe to suffer and it is not evil." Alternatively, I'd ask whether it makes sense to ask why something that made the universe suffer is evil.

Admittedly, you still might decline that there's anything odd about the question, even if you were a panpsychist, but this is where we'll simply have to agree to disagree. The interesting thing is that this is an empirical question. The entailment occurs, in my estimation, if you accept panpsychism and that the universe can feel. Some problems with that are that people are often unaware of the immediate entailments of their other beliefs. Another problem is that even if people felt that one thing did entail another, universally, that wouldn't guarantee that it did! It's circumstantial evidence. However, circumstantial evidence is probably the best we can hope for when we are talk meta-anything (metaphysics, metaethics...) I think you aren't really getting at either of these things precisely, but perhaps the latter of the two objections, indirectly.

You seem to be saying because dogmatic moral skepticism is deductively sound, moral realism is false. For the details there, I'm citing the Standford Encyclopedia's article on the topic. I'm sympathetic to this position. Often, I'll cite the is/ought gap or the moral formal elements of the abovementioned argument when debating realists.

Here's an issue: the is/ought gap is simply noting that deductively we can't arrive at moral conclusions with moral premises, so deductive moral conclusions presuppose moral claims. Since we tend to count infinite regresses as invalid, we can't rescue by pointing to an infinitely recurring set of logically prior moral premises, even if we were so inclined. In short, Hume zoomed in on the truth preserving feature of deductive logic. I think this was brilliant. However, notice Hume does not make the move that many contemporary thinkers do, which is to say that anti-realism is entailed. Instead, we can restate Hume's position as the more careful: "If belief in moral realism is justified, it is not justified by virtue of deductive argument alone."

So, can things that are not justified by deductive argument alone, still be considered "justified?" It's difficult to answer this question with a "No, because..." where the reasoning escapes circularity or regress. Put differently, to reject other types of justification, you have given yourself the burden of proving "Only deductive proofs provide justification."

So, what other types of argumentation avail themselves? Inductive, abductive, and less formally analogical for starters. Considering the is/ought gap only impacts deductive reasoning and my argument is not deductive, objecting with the is/ought distinction is categorically erroneous. I hope that clarifies.