(I'm one of the moderators of that group.) I don't think we've tracked the exact numbers, but I estimate that we approve about half of posts. Some others we refer to other groups for specific topics - for example we're referring most coronavirus posts to the coronavirus group right now. We reject some posts that aren't relevant enough or that don't meet the bar for what we think readers will find useful or interesting, which we recognize isn't a firm category. 

Because we have two moderators vote on each post, it can take us a few days to process a post - sorry for the delay.