I think most people can comment on what they like / dislike without being able to reproduce it themselves - examples
Art - many people can appreciate sculpture but cannot do it
Clothes - My wife loves them, but can't make any
Sports cars - many can drive them and suggest improvements but not able to implement themselves
Politics - enough said - many who do it can't and many who would like to do it can't either
Writing - I know when I've enjoyed a novel but couldn't write one
and so it goes on... but does any of it mean we can't express an opinion or that we should say nothing until proven in some way by somebody else that we have reached some 'arguable' status?
An opinion is an opinion - be it from a learned specialist in a subject or a layman. One may hold more credibility in certain circles (factual based on proven theorem with demonstrable repeatability), but in subjective review each holds it's own weight.
Provided somebody gives some rationale to go with the comments then it doesn't matter what their personal skill level or tastes are.
So for me it's a no..
Phil