I’m 46, diagnosed 3 years ago, symptoms for 7+ years. My symptoms are limited to my dominant right side. I have used dictation software on and off for about 7 years. I use it more towards the end of the day when my hands are fatigued which exacerbates the bradykinesia and rigidity.
I used Dragon Dictate for Mac for many years. The Windows version of Dragon software is vastly superior, so much so that Nuance (parent company of Dragon) suddenly discontinued the Mac version of the product via a press release. The Mac version still works fairly well, but there are no guarantees, and it’s no longer for sale for the Mac. The Windows version continues to thrive. It is very pricey but is leaps and bounds better than the alternatives. I now use the Windows version via a virtual machine on a Mac.
Apple Dictation should greatly improve *fingers crossed* with the new accessibility features (follow the link and watch the video under “Accessibility”) in the upcoming fall release of their new macOS Catalina operating system. There will be new accessibility features in iOS 13 for iPhone and iPad as well. I’m optimistic and thankful that Apple continues to dedicate time and energy towards improving accessibility.
I have tried most of the others you reference and they weren’t robust nor accurate enough for me.