Subscriber makes sense for a default WordPress role since WordPress was just for blogs, so the default registrant role would be a subscriber to see your blog posts.
https://codex.wordpress.org/Roles_and_Capabilities
Try creating a test user by manually doing so with an additional email you may have in the WordPress Register form. Then see what the forum role is. If it is blank still, make a test forum post to see if it changes.
You can also try some troubleshooting if something is messing with the forum role being set.
Troubleshooting
Thanks for the reply. I made a test account and did register via the Forum register page and it works as it should. These users (again likely all bogus) just registered as blog users (subscribers) so that works as it should as well.
Be nice to be able to not allow blog registration and allow forums but not a huge issue.
Thanks again.
I have a similar issue I think ..
I’m on bbpress 2.5.3 and wpress 4.3.1 set up as site, blog, and forum.
Regarding registrants roles, all Participants are Subscribers.
Yet some Subscribers have blank/no role for the forum.
Does this mean that a Subscriber doesn’t have access to the forum (if they’ve created an account via blog replay first) ..?
I’ve tested but can’t seem to determine the process. Sometimes I get a new registrant/user row but all fields are blank .. not trying to ask multiple questions here but want to include that if it helps diagnose what the issue is.
Thank you for any help!