“Obviously”?
Are you a navi? do you have ruach hakodesh? I am not, and do not. Therefore, when people make claims I ask for proof.
“Actually you are!”
No, Im not. Rav Moshe never ruled anywhere that smoking is an absolute Issur despite claims to the contrary. That his Sons and Talmidim say that he would nowadays is not the same thing and stating that Rav Moshe ruled it is an absolute issur. THEY are ruling it is an absolute issur and state that he would agree with them.