I agree with Jennifer, it shows commitment, but then whose to say that a wedding ring may not have been lost or with time, no longer fits? Someone could be allergic to metal! It's a symbol of commitment but it does not necessarily command respect.
No. I don't see why I should have any more respect for someone who's married. All it tells you is that they're in a comitted relationship. It doesn't make them smart, likeable or a good person.
I'm married myself but rarely bother to wear my rings. They're annoying when I have to wash my hands a lot (water collects around the ring and irritates my skin) and I don't want to lose a stone out of them while doing housework.
People 'earn' my respect, over time.
What jewellery they wear is irrelevant.
But, I've noticed, over my long life, it's very easy to tell if someone has NEVER been married, either male or female.
That just have a certain 'look' about them, as well as many other tell-tale signs.