Acapulco has been ****** for sometime. Not sure why you are trying to tie this Acapulco article to Cancun. I feel safer in the hotel zone at Cancun or at the Royal Haciendas in Playa del Carmen then I do near the Hennepin and 4th/5th/6th Ave areas in downtown Minneapolis anytime outside of 8-5 work hours. With that said the recent news stories on bad booze and such is a little concerning but I am not at all-inclusives and not drinking booze, only beer.
Here's what the state Department currently says about the two areas:
Guerrero (includes Acapulco, Ixtapa, Taxco, and Zihuatanejo): Personal travel to the entire state of Guerrero, including Acapulco, is prohibited for U.S. government personnel. Self-defense groups operate independently of the government in many areas of Guerrero. Armed members of these groups frequently maintain roadblocks and, although not considered hostile to foreigners or tourists, are suspicious of outsiders and should be considered volatile and unpredictable.
(In other words, don't ******* go there.)
Quintana Roo (includes Cancun, Cozumel, Playa del Carmen, Riviera Maya, and Tulum): U.S. citizens should be aware that according to Government of Mexico statistics, the state of Quintana Roo experienced an increase in homicide rates compared to 2016. While most of these homicides appeared to be targeted criminal organization assassinations, turf battles between criminal groups have resulted in violent crime in areas frequented by U.S. citizens. Shooting incidents, in which innocent bystanders have been injured or killed, have occurred.
(In other words, be aware of what the hell is going on around you just like you would in a big city in the states and don't hang around in Cancun proper, stay in the resort/hotel zone.)
I'd be more concerned about areas with more cautions that are popular for Americans like Los Cabos and Puerto Vallarta.
All the Mexican state travel warnings:
https://travel.state.gov/content/passports/en/alertswarnings/mexico-travel-warning.html
