I guess also, for enboy, some people think there is a difference in between demi-boy and enboy, whether it be miniscule or not, and that might matter for some people
For cat/pup gender, not all people who identify as such would want or feel connection to the label furry. Like how some non-binary people choose not to identify as trans, while some do. And some cat/pup gender people also have a binary feeling to go with it. As for the definitions, in the links I gave you it didn't mention personality being apart of it. Also, the label for cat gender was created by an autistic person, to better describe how they feel in terms of gender. Basically, mostly neurodivergent people would use these labels as they don't understand being a boy or a girl. That's not to say that others can't use the labels. However, I would like to agree to disagree on this.
Just like some people prefer bisexual over pansexual, despite technically having no difference, some people prefer enboy over demiboy. As for cat/pup gender, how I've seen it explained is that imagine you don't understand gender. Everyone says you are a boy or a girl, but how do you know? Then one day, you see a puppy walking down the street. Everything about it just matches how you felt inside. That's what pup/cat gender is about. (Please note I've only had this explained to me so I could be slightly wrong)
Not all enboys identify as demiboys
Cat/pup gender is valid, though most queerphobic people use them to make fun of the trans community
Fictoromantic is definitely valid and I have seen someone who identifies as fictosexual (sexual counterpart) on here
Since I couldn't find anything on venusfluid I can't say anything about it
