No, nobody uses a 3-strip/3-sensor approach anymore. It was used in the early Technicolor process, and was revived during the digital era with cameras like the Minolta RD-175, and it lingered on in cine cameras for a while longer, but nowadays almost everyone uses a bayer-filter approach (or a very similar one - there are several proprietary alternatives for the mosaic layout that claim various quality improvements).

The only similar thing nowadays is Foveon sensors where you have 3 color sites stacked on top of each other, but Foveon didn't really have the money to keep up with the arms race and nowadays the modern sensors are far better even though they do have to apply a low-pass filter to avoid mosaicing. When you have many, many, many nodes of improvement past the Foveon sensor, that stops being a big deal.

It was also never particularly widely adopted, because none of these things are new - it was a tough sell to market a "really high color-resolution!" 5mp camera going up against 20mp filtered sensors and 50mp unfiltered sensors even 10 years ago.

Interestingly though, the Foveon approach is similar to film. Film has multiple layers and all are exposed at once. There's no denying bayer is sort of weird. It's just very expensive to be the odd man out doing your own sensors. "Good enough" usually wins, Foveon may be betamax but bayer is VHS - and I use that analogy knowingly, in the sense of Betamax also doing key features worse in areas that consumers care a lot about.

Consumers camera use a Bayer colour filter array because it is cheaper and more compact. Demosaicing is performant enough for most consumer applications that it is hard to justify for anything than scientific applications. As a matter of fact, even Motion Picture cameras, e.g. ARRI LF, are using a Bayer CFA.

There is one model still sold by sony using these! https://pro.sony/en_GB/products/shoulder-camcorders/pxw-z750

All the others have now switched to bayer sensors.

There’s also a stacked sensor version.

https://en.m.wikipedia.org/wiki/Foveon_X3_sensor

Not plenty, “3CCD” cameras exist but are rare and mainly used for industrial inspections and TV broadcasts. Some old home video cameras did use it but not anymore.

I don't know of any consumer cameras that do this. Some manufacturers use a different filter on some models, Fuji uses an X-Trans filter on some models which in the past can cause issues with some software demosaicing.

If they do, that has to be limited to "broadcast" cameras. Digital cinema cameras all pretty prominently use a single sensor.

Nope, Bayer is the norm, but there's still some Foveon cameras that are typically rather slow to produce images.