“All opinions matter” said the poster in the subway, trying to get me to take part in a survey. Would that it were so simple. Opinions are quickly adopted, easily changed and rarely based on facts. So I’d disagree with that poster and say that your opinion doesn’t matter at all—unless it’s an informed opinion. That is, one based on facts.
For example, when talking about vaccination, it is often asserted that there are two sides, pro and con. And that both positions are valid opinions. But being against vaccination is not a valid opinion, because it’s not grounded in facts. There are no rational arguments against vaccines in general. Vaccines are an astoundingly useful achievement of science.
The false balance between informed opinions and uninformed opinions changes a rational discussion between informed people to an irrational discussion between opinionated people. For me, the transition from having opinions to having informed opinions meant being less opinionated and more often stating “I don’t know, I’ve not seen any facts point either way.” I can only wish for everyone holding uninformed opinions to do the same.