That and apparently millennials (and younger) not wanting to spend an insane amount of money on hotels and alcohol to gamble in a smokey casino when they can do it on their smartphone.

Vegas used to be cheap kicks but now everything there costs, and it costs a fortune. The quality of everything has been reduced drastically as well. Combine that with the fact that America's brokest generations just don't have the free cashflow to sustain their parents lifestyle of random trips to Vegas to blow their money, loss of foreign tourism, and you get a pretty ugly outlook.