In order for an opinion to be worthwhile it needs to be earned.
Everyone has freedom of thought, a right to form an opinion, and the right to express their opinion.
But opinions should have consequences.
An earned opinion is one in which the consequences are understood and accepted.
You can earn an opinion only through action. Whether action means a deep understanding of the material through direct usage or intense study of the subject.
The opposite of this is the stream of uninformed and inconsequential opinions you find online.