The camera's I've owned (Canon and, in more recent years, Olympus/OM System) all could do RAW, JPG, or RAW+JPG, or in some cases cRAW+JPG, with several quality

The camera's I've owned (Canon and, in more recent years, Olympus/OM System) all could do RAW, JPG, or RAW+JPG, or in some cases cRAW+JPG, with several quality settings available for the JPG side. But remember, on a camera you're wanting to maximize battery life, image quality and certain key performance metrics. The OM-1 Mk II can burst up to 120fps of 20 megapixel images with locked focus or 50fps with continuous AF. Thats a huge amount of data to capture, process and write to media. I think we want cameras to optimize for that. It's trivial to dump the resulting files on your computer and then convert between formats to your hearts content.