No experience - no opinion rule?

Reading this family issue thread I couldn’t stop thinking of something I always want to ask.

If one never caught their partner cheating - does it mean they can’t have a say on a subject?

If someone never been divorced - does it mean they can’t talk about divorces of others and say ‘I would never leave for children sake’ etc.

If somebody never been coupled or single does it mean they should keep their feelings to themselves?

I kind of agree. But if you have indirect experience, you're the child of divorced parents or someone used you to cheat on their partner with - you can offer your opinion from a different angle.