HDR imaging is not a certain look. High Dynamic Range, has a relative term "high" - high compared to what? Compared to the a printer's ability to print? The 8bit monitor? Or the 8bit jpegs? Or the 12-14bit cmos sensor?
If we choose the typical jpg/monitor, then the RAW file IS HDR - and it is a monochrome HDR image even. You don't "make a HDR from it". It already IS. And your RAW converter and the built-in camera software (when storing jpgs on the flashcard) turn this monochrome HDR image into low dynamic range (8bit per channel) through bayer interpolation and (linear and nonlinear dynamic range transformations known as) tonemapping (and other operations, e.g. neighbourhood operations also known as) sharpening, noise reduction, and highlight management. In good converter software, it lets you play around with which details to preserve, compared to the take-it-or-leave-it direct-to-jpeg-one-size-fits-all.
If you consider HDR to be "higher DR than the typical sensor" (which is how industry and researchers see HDR) then you also cannot turn a single RAW into a HDR image. you need the multiple exposures to see more dynamic range (saturation divided by noise floor), which you then combine into a floating point image - or perhaps at 16 bit image. which you cannot see on the monitor without the above mentioned transformations. However, since you have all the dynamic range in the image, you have more choices in the 16bit-2-8bit processing, where you squeeze and expand certain areas of the dynamic range.
If you want higher dynamic range you can also buy machine vision cameras with 100-120 DB (versus ~70 db) that has certain tricks to create 16bit images; multiple readouts, 2 sizes of pixel cells interleaved, one of the green pixels in the bayer pattern being twice as sensitive as the other, etc. They are very expensive though, and have no "photography" branding (features, lingo, only the most simple tonemapping - gain, wb and gamma). Pure dead honest raw imagery (which you then can tone-map as you please).