Ok, you can not answer the OPīs question, because there are tons of All Inclusives in Cancun / Riviera Maya Area that serve all budgets.

Lets put Cancun as an example: Live Aqua vs Holiday-Inn Cancun Arenas. One has two designer restaurants while the other can be bought as EP or as AI and is way down in the Good Food Scale.

Once after this example, I can only tell the OP that Spanish All Inclusive Hotels have transition into the very good food with the years. Now, Riu and Riu Palace (both, Cancun and Playacar) have great food considering there cheap rates. That chain is one of my favourites now a days, and try to book with them as much as possible when the price is low enough.

On the other hand, when traveling with company to upscale resorts in Rivera Maya / Cancun for business, Live Aqua, Velas and ME, i have found food to be amazing and so as alcohol.

So all in all, as other FTerīs said, it sometimes depends on the type of hotel (and not on price) to know if the food will be good.