Wondering whether a bent penis responsible for low sperm count?

No it isn't: Sperm is produced by the testicles, pass through epididymis, vas deferens ; ejaculatory ducts into urethra just beyond bladder neck. Then sperm contained within semen pass down the urethra which will be curved more than usual if you have a bent penis, however, will not affect sperm count. Suggest you consult a urologist if bent penis is otherwise a problem.