Why would I want to remove nofollow from user links?

I think I understand the purpose of adding rel="nofollow tags to links in user posts: it’s basically telling search engines “this link is not endorsed by this website” in order to make spamming (or rather spamexing) less attractive. So it makes sense to do that on any forum.

But discourse allows me to exclude certain domains from that policy using the exclude rel nofollow domains site setting. I can also turn it off all together by unticking the add rel nofollow to user content setting.

But I’m wondering: why would I want to turn nofollow off at all? Is it just to help search engines distinguish between good and bad links (I guess that’s why TL3 users are exempt from nofollow by default) or is there any benefit for my forum? Which domains have you exempted (except your own)?

You would want to allow links from your support forum to your documentation site, so that your documentation site could get SEO benefits from the links.

You let tl3 members link to their sites so that they get the benefits of links too their site in appreciation for the free support they they provide.

Contriving a reason that you want anyone to have the ability to have links followed if something that I can’t do, but someone wanted it, and it wasn’t hard to implement.