Good points. There's also a pretty big self-help market emerging online, so many youtubers and people making ebooks. It's also likely that a lot of awareness will be given to those psychological issues.
You're right about the confidence thing, I've never known any women who think of vibrators as a replacement for a flesh and blood man in their life. The sentiment is only expressed as a joke. We are all entitled to make mean jokes about sex and love.
It's all in men's minds...and it would be very unattractive to have a guy feel threatened by a sex toy so it's kind of a self-fulfilling prophecy. I can only imagine the worst case scenario of a man who thought it counted as cheating, maybe that's the equivalent of a super jealous woman freaking out over casual porn use. Or a man who only wants his girl to watch porn with cocks smaller than his lol
Besides, using one alone can't compare than with someone else holding it. So there's lots to gain there.
Insecurities are the most unromantic, unsexy addition to a couples life.
I agree that the insecurities are super unattractive. Some people are really insecure and oftentimes that surfaces as jealousy.