GSA doesn't obey "Skip Nofollow"

I ticked that but it still posts on nofollow sites...Why is that?

Did you really look at the checkbox? It says "Try to skip creating nofollow links". It is not 100%.

Yes if you have a ratio of 10 do-follow external links and just 5 no-follow external links, it's placing a link as it sees a chance to have the link do-follow.

I use all platforms and probably average 80%+ do follow. I almost wish there were more no follow links to be a little more natural, but I'm not complaining.

Just untick that option, it will lower your submissions.

when you are selecting platforms just right click and select: Uncheck engines with nofollow links.