I was recently looking at the survey article of Fu on symplectic resolutions which has a number of open questions and conjectures at the end. (I think one of these was existence of a classification of when symplectic singularities admit symplectic resolutions, which is discussed on other MathOverflow questions).
Another perhaps simpler question which was mentioned was whether there is a proof that Coulomb branch varieties are always symplectic singularities. Has any progress been made towards a proof of this or is it of similiar difficulty to the other question I mentioned?
Edit: I'm slightly surprised that no-one has answered this question. It seems like people who work on these types of thing are not very active on Math Overflow for some reason, I'm not sure how that is meant to help people who wish to learn more about the subject.