To be frank, I really don’t get the appeal of fan-insert characters even if I attempted doing so when I was younger but that’s when I was looking for a role model. Still I’m probably wrong and biased about myself.
I should say that I really don’t get the appeal of fan insert characters, especially they’re blatantly a lot like the audience unless if it’s done in a scathing or satirical manner. It doesn’t mean that they’re always into fan fiction but they don’t seem to be interested in anything else.
In real life, even if you have people who idolise their favourites do outgrow them and have other things to do. Their paths diverge over time. That might be something that superhero stories have attempted before but not much success at it.
In the logic of superhero stories, the fan character who becomes an heir is fated to not only imitate and inherit his/her predecessor but also parallel him/her which gets more obvious in later stories. Jay Garrick pre-empted Barry Allen, who not only idolised him but also shared similar abilities and scientific occupations.
Wally West would parallel him all the more by sharing similar fates, having families with speedster children, getting speedy sidekicks and having girlfriends who get assaulted by their doppelgangers.
Then you have the fan-insert character who isn’t an heir but remains subordinate and has so little room for anything else to do that s/he is an audience conduit for the worse. Cisco Ramon is like this, even if he’s not always this way in canon.
There is room for characters who do idolise but have paths, interests and occupations of their own but they’re increasingly rare. In superhero media, they’re almost always bound to be proteges who regress, interchangeable and disposable proteges and heirs and fan insert characters that never go anywhere else.
In real life, most people outgrow whatever they’re interested in and idolise. Maybe not exactly since some can go back and forth but when they get interested in something new to do and care about, they will outgrow their old hobbies and interests.
Even those who get to work with big name veterans will always have other things to do and care about as time goes on. There lies the problem with fan insert characters, heirs and proteges. They don’t really grow up, they’re painfully static in that they never actually become their own characters for long.
They never outgrew their obsessions and mentors like what real life people do. They have hobbies and interests but you hardly see them take up anything new. They also don’t do anything new either.
Which is why you don’t see Felicity Smoak actually hook up with someone else. The people who identify with her a lot wanted her to hook up with Oliver so badly that the quality and ratings declined.
Cisco Ramon could outgrow his association with Barry Allen. But it’s uncertain at this point. Ditto Agent Phil Coulson, who is best remembered for cheerleading Captain America.
Even those who have a chance to be with that celebrity don’t remain associated for long. Some people don’t remain friends for life and it happens fairly often in reality. They have other things to do simple as that.
I could call myself a fangirl and detest those characters is because they never speak for themselves. They don’t outgrow things. They remain childish and static. I don’t get the appeal and that’s my opinion.