In my 16 stays this year across multiple brands (mainly LC, W and StR but also 3 Sheratons) I’ve had bottles of water in every single one of them and staff was always happy to bring more, sometimes even without me requesting them - if they noticed that I used most of them, next day they’d just bring more.
Personally its one of my favorite hotel perks, thanks to it I have almost entirely switched to drinking water rather than various sweet drinks which comes with a lot of health benefits.
Right now I’m staying in a junior suite in LRM Shanghai and the room had 6 bottles of water waiting for me on arrival.