It's all float value arrays with metadata in the end. Most camera sensors are pretty similar and follow common patterns.
DNGs have added benefits, like including compression (optional) (either lossy or lossless) and error correction bytes to prevent corruption (optional). Even if there's some concerns like unique features or performance, I'd still rather use DNGs without these features and with reduced performance.
I always archive my RAWs as lossy compressed DNGs with error correction and without thumbnails to save space and some added "safety".
Nitpicking correction: The sensors give you a fixed number of bytes per pixel, like 10 or 12 bits per pixel. This are unsigned integers, not floats.
Typically you want to pack them to avoid storing 30% of zeros. So often the bytes need unscrambling.
Any sometimes there is a dark offset: In a really dark area of an image, random noise around zero can also go negative a little. You don't want to clip that off, and you don't want to use signed integers. So there typically is a small offset.
DNGs have added benefits, like including compression (optional) (either lossy or lossless) and error correction bytes to prevent corruption (optional). Even if there's some concerns like unique features or performance, I'd still rather use DNGs without these features and with reduced performance.
I always archive my RAWs as lossy compressed DNGs with error correction and without thumbnails to save space and some added "safety".