Hi
Linking image make it necessary to get a approval from a moderator if you are new on the site, like it’s in Technet/MSDN actually.
The difference is on Technet the post got published without the image, while there it get inside a moderation’s queue to get published.
I can’t answer at how much reputations the system thrust you, so joining a image no longer need moderator right, but maybe a employee can answer for that.