Elvis living to 80 basically predicates that he kick the drugs and improve his unhealthy lifestyle. The best way for this to happen would perhaps become a born again Christian. Elvis was already fairly religious but concern from his family leading to an intervention would be the perfect combo.
Elvis would have some difficulty remaining a top cultural force though. His audience was aging already, so as said he'd probably experiment with country, do more gospel extra. Would still be a highly respected figure in the industry though.
Might Elvis go totally into gospel music?
Would ATL Elvis have collaborated with Michael Jackson?
Ooof, would he be as brain damaged as Brian was?My favourite pod for Elvis living longer still is him becoming a patient of Dr. Eugene Landy. Call me evil, but it is.