I think in the paper they are talking about serializing the entire object as a single string key that needs to be loaded and written all at once even to do simp

I think in the paper they are talking about serializing the entire object as a single string key that needs to be loaded and written all at once even to do simple things. Nested data structures are definitely going to be better than that but they also do have some caveats. If you really want to nest arbitrarily, take a look at RedisJSON, but I would recommend to stick with vanilla structs as much as you can. More often than not you can quench your thirst for nesting by good use of key prefixes.