Not all first topics and posts become Unapproved. Only spam suspected entries are going for moderation. Please install Aksimet to make this wpForo Spam Control more intuitive. Spam suspicion level can be decreased in Dashboard > Forums > Tools > Antispam admin page to something like this:

• Spam Suspicion Level for Topics: 30    
• Spam Suspicion Level for Posts: 30

Also if the topic (first post) is unapproved, all posts of this topic becomes automatically unapproved (post author doesn't matter). Because you can't see a post if the topic is unapproved.

You can approve new topic and posts in Dashboard > Forums > Moderation admin page. This works like WP native comment approving process. If wpForo suspect some topic as spam it makes unapproved to allow you review before it becomes published on forum. Only spam suspected topics and replies become unapproved, and only new registered users topic and posts are under spam control. Please read new wpForo 1.2.0 release changelog before updating and using it:

https://wpforo.com/community/wpforo-announcements/wpforo-1-2-0-is-released/

I think it worth to spend a few seconds for topic approval instead of having spam topics on front-end.

In any case if you want totally turn it off, you can set "No" wpForo Spam Control in the same admin page.

Also please read this support topic:

https://wordpress.org/support/topic/new-topics-and-post-without-moderation/#post-8977005