exposure - Do colored LED lights produce less illuminance than traditional spotlights?

I'm shooting theater plays and starting to shoot some alternative fashion shows.

Many colored lights these days are LEDs, not white + gel as they used to be. Let's simplify things a bit and consider that an inexpensive red (or blue etc, but just one pure R or B channel) led light used in a theater will have almost 100% of its power output concentrated on a spread of red frequencies. Do correct me if my assumption is wrong.

Bayer matrix based cameras will have 4 photosites but 3 of those (2G + 1B) will filter out red light. Same for blue. However, those 3 other photosites will still generate noise.

Would I be right in saying that under such conditions I'm essentially dividing any latitude my sensor has by 4? In other words, to get to the same perceived amount of subject brightness I'd be compensating with +2 EV (or +4 EV ??) on aperture, speed or ISO?