I was surprised to see that StarForge wasn't on this list, and after looking into it I think it's because after it was delisted someone else published another game named StarForge. I wonder how common that is.

What are the uniqueness requirements for titles, For the most part people are reasonable and don't want to stomp on each others names. however there are bad actors and this is usually where trademark law comes into play to help protect the name, but does steam impose additional uniqueness constraints on top of this?

That might be a fun list, games with the same name.