Of course he is not going to think he's missing anything he had no choice in getting his genitals mutilated and he's never experienced having a foreskin and probably never had sex with a man who has a foreskin either sucking off a guy, stroking his dick, or bottoming.
A guy that's cut saying he's not missing anything is akin to someone who has had a lobotomy or ECT (electroconvulsive therapy) claiming they are not brain damaged at all.
A dick that's cut is no more "Clean" than a vagina or penis that is completely unmutilated and is fully functioning. It does not matter if someone is cut or not when it comes to cleanliness. What matters is if they practice basic hygiene and wash with soap and water daily. I have been with guys who are cut who had nasty smelling dicks because they thought they did not need to wash daily since they were cut. We did not have sex.
Circumcision of infant boys is child molestation.