Discourse by default appears to put some rather parochial constraints on newly signed up users:
We want people to be able to sign up and freely provide feedback during reviews with lots of links, and we have moderators to deal with unproductive posts, so this automated screening seems unnecessary to me. Can we disable it?
This is an anti-spam measure. I can probably increase the number though.
Raising the limit sounds good. I'm curious, do we have enough of a spam problem for this to be an issue? This could be me living in ignorant bliss because you all are doing your (much-appreciated!) jobs well on the backend, and there's certainly value to defense in depth before problems start, but as it looks today it seems to me like this restriction is more likely to impede new contributors than it is spammers. Another thing we might be able to do, if Discourse allows, is to customize the error message, so that instead of just being told "new users can't post more than N links", the message also tells them why, and who they can contact to bump their trust level if they have a legitimate reason to post many links.