Anything posted on here is effectively "plastered all over the Internet", as this is an open forum that anyone can view most areas of.
You can have a closed group on Facebook, Instagram etc, where only the people you choose to share pics with get to see them. So in many ways more private than this site.
No.
Good photos that portray shooting in a positive light are well worth posting.
But you have to learn to view them through other eyes before posting.
I liken it to when I was a part-time journalist, writing magazine articles every month. Before sending in a piece for publication I used to print it off to proof read it, not do it on screen, and I'd sit down in a comfy chair with it and a cup of tea, so that I could "be" the person who would ultimately be seeing it in the magazine, and read it through their eyes. It had to be right for them, not just right for me. And ultimately that sometimes meant compromising on some aspects.