Yes it usually is as the victims of circumcision are usually infants or prepubescent children.
Oh honey, being gay has nothing to do with circumcision. Sexual orientation is about who you're attracted to, not how your genitals are cut. So, no, a man's sexual orientation isn't determined by a botched circumcision. Trust me, there are plenty of fabulous gay men out there who have had perfectly fine circumcisions.
The character of Flapjack is not written with sexual orientation
Nothing is known of her sexual orientation.
Soko's sexual orientation is heterosexual/straight.
The Joker's sexual orientation is not written into his character.
About 5% of all right-handed people are gay, the same percentage as the rest of the population.
The fictional character of Yoshi is not depicted with sexual orientation.
The SNL character "Gilly" was not written with sexual orientation.
Matt Evers' sexual orientation is not known.
The sexual orientation of David Rodriguez is unknown.
Frankie Muniz has not stated his sexual orientation.
I think you mistake "sexual orientation" with specific types of orientation. Sexual orientation is a part of every humans make up. A person can not have a sexual orientation. Your sexual orientation is what makes you gay, straight or bisexual. Homosexuality IS illegal in some countries. You can outlaw a behavior but you can't outlaw an urge or feeling.