Players have choice, even more so in sandbox, non-linear megadungeon. No one forces them to spend time in any room or even to open the door to any room. If they chose to spend 3 hours in/out of game time searching and futzing with every brick in wall and piece of garbage they have no one to blame/thank other than themselves.
If uninterested they could open door, see nothing, move on. Could even preempt "dressing description" by asking DM "Any monster, any obvious loot? No, we close door.
I've personally witnessed many people accustomed to railroads and storybased games struggle when given choice. Often either doing nothing waiting for plot to advance or doing everything (e.g. exhaustively searching every room) assuming it all must be important part of plot or it wouldn't be here.
Whether a player likes sandbox or not has to do with the player (and their expectations) more than with the sandbox. This is why it's very important to explain sandbox and "train" players how to make choices. Or, help them identify sandboxes just aren't the type of game they like and live and let live.
I was skeptical at balance, you lost me at "monster power curve". [context]
RPGs aren't games that require or benefit from "balance" or even rules in the traditional sense. they have an intelligent, adaptable referee who will outperform any set of rules or mechanisms hoped to provide balance. The referee is not just another player, they are the game. I don't mean that in an egotistical way. But rather referees are what distinguishes a RPG from say an adventure boardgame or an MMO themed skirmish game. And those are fun types of games. They aren't RPGs. (Miss)using the label leads to mis-matched expectations and shit-storms like "Are empty rooms teh Awesome!".