You say that, and I said similar things in the past, but Marino was just the forerunner of today's passing offenses. Miami could put up crazy pass numbers because they abandoned the run and exploited archaic defenses. There was no "Tampa 2" until the 90s. D coordinators hadn't yet figured out how to properly lock down long pass plays with a top heavy zone. There was no such thing as zone blitzing either. Yes, DBs could chuck guys downfield, but teams stupidly actually lined up the strong safety over the TE and left him there, as if he was required by the NFL rules to be on the "strong" side.
Look at Clayton/Duper's receiveing numbers from the 80s. Both averaged like 20 yards a reception. They were catching balls in stride and running to open grass. They weren't putting up Julio Jones 15 reception games. Both averaged around 4 receptions a game, neither hit 100 catches ever, but both were 1000 yard guys every year. What does this mean? It means Marino would simply eye fake the safety, he'd bite because he's horrible and on the 84 Jets or whatever, and he'd throw a gimme 60 yard TD. That's how you get to 48 touchdowns in the 80s.
Neither sniffed 100 receptions. Duper never had more than 71. Clayton had one year with more than 73, later in the 1980s. These werent possession guys. He simply threw deep ball after deep ball like a 13 year old playing Madden. It worked because the defenses were primitive and still played run first. Also, Marino had that awesome fast release, and Miami really did have a good pass blocking O line. Fewest sacks against in the NFL helps.
9 yards per pass attempt over the course of a whole season. Dude.