Over Opinionated people are those who resend any other view on their believes, like religious lunatics or somebody otherwise biased to carry on their own agenda no matter what.
In the lack of knowledge ignorance prospers, and while it takes a character to seek better understanding, most settle with opinionated views out of convenience, is sad but natural course of things.
Only the opinion open to judgement is the opinion worthwhile standing by. Anything else makes you opinionated and simply ignorant. In this context being over-opinionated means over-ignorant, fixed on the idea that takes you over against your better judgement, and alienating to others.
Say, you order a pizza after a long day, the doorbell rings, you rush there to open, drooling, feeling the taste of it, only to find Jehovah's Witnesses at your door, damn. So what do you do? - You stand there, pretending you are listening to their BS until the pizza man comes. After all, they don't care if you are listening just as they don't care what you think of it, they are over opinionated lunatics, no more no less. And unfortunately that's just the way it is, so you leave them be.
Phenomenally shitty, uber-crappy.
- How was that new movie?
- Turdtastic, I wasn't nearly drunk enough to enjoy watching it.