I am not coming at this from a "I don't want to pay housekeepers" angle. I just think it's ******** that very profitable hotels (until Covid anyway) were counting on guests to tip housekeepers rather than paying them a decent wage.
It shouldn't be a "count on tips" job as it isn't really a personal front-and-center service job like bar tending, valet, or waiting tables. In those jobs, tipping acts as an incentive model for good performance. But for housekeeping, they have to clean the room to a standard, there's really no variation, and they can't not clean your room if you don't tip (unlike a bar tender who can ignore you if you skip the tips).
You don't tip cooks, teachers, garbage men, HVAC people, and a whole host of other service jobs for various reasons. You shouldn't have to tip housekeepers so that hotel companies can pay them less in salary.