I found an answer that solves my question here:
Meta Title for Profile Pages w/ Yoast SEO
For those who want to noindex in particular the replies of all mebers just add
<META NAME=”ROBOTS” CONTENT=”NOINDEX, NOFOLLOW” />
to the “user-replies-created.php” in the folder
wordpress > wp-content > plugins > bbpress > templates > default > bbpress
Any other idea? Any feedback is highly appreciated!
Making member pages accessible for logged in users only is an interesting workaround. Thanks a lot for this idea.
Nevertheless I wonder if there is any option to add “noindex” as meta-tag to each member page instead of using robots.txt?