People about cosplay...
The only place it should really matter is in competition. Don’t enter a workmanship based contest with something that you bought or commissioned, and don’t take credit for the work of others.
That said, some contests have a category for commissioned or purchased costumes, you would be fine if you entered there.
Ancient peoples dressed up as animals and gods. They dressed up as powerful characters of myth and reenacted stories that were important to them.
Modern people do the same. On Halloween, people dress as archetypes of many kinds, At Christmas, you see people dressed as Santa Claus in the US, reminding us to be kind to others, even if we don’t put change in this particular pot.
Once, I was in an Indian restaurant and as I waited to be seated, I looked at pictures of a party at the restaurant. They had two people cosplaying Krishna and Radha.
I attend anime/manga gatherings and I know from talking to many, many people about this, that the drive to dress up as characters you love comes from wanting to participate more deeply in the narrative.
At Renaissance Faires, I was quite often told by people “this is my real self,” as opposed to the normal worker bee they were during the week.
And then there is cosplay as a sales technique. Booth babes are hired at tech and industry shows because getting a dorky guy over to the table takes work. Geeky folks are cynical folks, but a pretty girl will draw many men without working at it. Once they are there, they must of course be engaged and thrilled by the tech, but the hook is the girl. Or in a maid cafe in Tokyo, having someone be kind to you, call you “Master” and do your bidding feels good, even if you’re paying by the hour.
So, why cosplay? To engage with our mythical/narrative roots; to take on skills and powers that we don’t normally have, in the context of ritual – or fun; as a visual hook to drive commerce; to enjoy, for a moment, the thrill of being something else than we are or who we feel that we really are.
We may not all cosplay, but we all play dress up from time to time. Next time you slip into tux or a really nice dress, think about the cosplay you’re engaging in – what are you projecting? What makes this you different than the everyday you? What powers, skills, qualities are you pretending to have?
To me, it’s equally a tribute to the property that I’m making the cosplay from, and the art form.
One could say the same thing of not getting the appeal of creating any media – learning any instrument, painting a picture, writing a book. It’s creation and display – this may not be the same to everyone, but it’s definitely a big part to me. It’s also a way to meet new friends from all walks of life. I’m certain if you looked closer, a lot don’t meet the stereotypes of an overgrown kid. I cosplay with people in the military, aerospace, tech, and all walks of life. Conversely there’s people that do this for a living, myself included.
As someone that enjoys hobbies and media that was formerly shunned for being “too nerdy”, perhaps immediately throwing anyone that takes part in cosplay into the “you’re a man/woman child” box is a bit reductionist, and a little offensive.