You can't see it from any of the rooms I've stayed in. Most of the hotels face south rather than towards downtown Hong Kong. It is possible that some of the east-facing rooms on the high floors of the Hong Kong
Disneyland Hotel would have a view, but even then it would be a pretty sad view because the resort is so far from downtown.
IMO, it's not worth going into HK just for the light show--it's neat, but not THAT exciting--but it is absolutely worth going in for a myriad of other reasons (food, The Victoria Peak, museums, the bus to Stanley, etc.) and then just seeing the light show at the end of the day.