I concur with tbhv55.
When DR =100 at ISO 1600 and below, there is no reason for the raw files to be "much noisier" than the JPEGs.
Above ISO 1600 (which I rarely used on the original X100) it is likely FUJIFILM applies in-camera noise filtering to the JPEGs. The noise filtering, if present, would be in addition to the in-camera JPEG noise filter parameter. However it is also possible the raw files are similarly filtered in-camera as well.
At all ISOs a JPEG with the highest, user selectable, in-camera, noise-filter setting may appear to have a higher signal-to-nose ratio than a raw file rendered with no noise filter.
As ISO increases the exposure (signal level) decreases. The signal-to-noise ratio decreases. ISO amplification only increases the rendering brightness, not the exposure (signal level). The amplification increases the signal and noise levels by similar amounts. The difference between an in-camera JPEG with the maximum noise filter and a raw rendering with no noise filter will be most noticeable at lower signal-to-noise ratios (higher ISOs, less exposure). However using the an appropriate noise filter during raw rendering should result in images with similar signal-to-noise ratios.
As far as I know there is no in-camera raw file noise filtering at ISO 1600 and below.
You might compare results with DR=100.
In identical light take a set of JPEGs at ISO 1600 (or the highest ISO you plan to use) with all the in-camera JPEG noise filtering levels.
Then take two raw files. Expose one at ISO 1600 (or the highest ISO you plan to use). Expose the second at ISO 200. The second will initially appear very dark. In post-production increase the raw ISO 200 image's rendering brightness globally by 3 stops. Then compare which image has the best signal-to-noise ratio in the shadow regions.
Of course you would want to compare the raw to JPEG as well.
For the original X100 I decided ISO 1600 was the emergency maximum for color work. ISO 1600 was acceptable for B&W. I only used raw files and rarely exceeded ISO 800.
