The rules for AFCI are fairly new and will be massaged in the future, as more information is gathered.
As for now it is almost "experimental" in nature. What I mean by that is the requirements are for bedrooms as some "information", whether correct or not, has been presented that fires tend to start in bedrooms more than not. And they will be looking at studies to help further decisions in the future.
The studio/one room scenario might not have been considered. I do not see the harm of having it all protected by AFCIs, but that would require GFCI protection at the countertop receptacles located at the receptacles, as AFCI do not provide the proper type GFCI protection as per NEC.
For now I would permit the installation with or without AFCI protection for the kitchen area.
Remember this is strictly my opinion!!!