I have released I think 6 games on Steam at this point (I am not totally sure the total) starting at the age of 13. You got this dawg.
I am 22 now, almost 23. Maybe you are older, maybe you are younger... it does not matter.
The only downside of Steam is you might want to either wait for that 10k wishlist or whatever, or just release it when you can. A lot of games do not get sales because they are bad. I do not believe your game is bad.
There is no reason you cannot sell it on Steam. In fact, I will be angry with you if you do not.
Just do it.
I would also be curious to see your itch analytics sometime :)
If you wanna dm me: georgehennen on X, george.c.r.hennen@gmail.com is my email.