Having stayed at all the Riviera Maya resorts apart from Banyan Tree, I would not say that any of them were particularly good on the food front. Rosewood was awful in every way, MO was much better, but not outstanding.
Surprisingly, the best meals we had were at The Tides (not now, though!!!

) when Exec Chef, Cuppertino Ortiz was there and the GM was Julian Smaldoni.
The other memorable meal was at Maroma (Orient-Express) in El Sol, but entirely due to Argentine Chef, Guillermo Javier Gomez and his Yucatan sous chef, as Orient-Express is not normally known for its food. Of course if this chef has now left, then it could be quite a different matter.