[How to turn off front command dial?]

I cannot find a setting to disable the dial completely.

You could set the three slots for the front command dial like this (Menu > Wrench (Set Up) > Button/Dial Setting > Command Dial Setting):
Slot 1 Aperture
Slot 2 None
Slot 3 None

Then switch to Slot 2 or Slot 3 using the setFn button (setFn default is the button in the viewfinder mode lever on the front) press and hold it, then select Slot 2 or 3.

(FWIW I am using an X-Pro3 to work this out).

I hope this helps.

[Has the X-Pro3 been a success?]

I think the answer to this question depends on the criteria used to measure "success". And also success for who? For Fujifilm? For you? For me?

I can't find any sources that breakout sales for Fuji cameras by model, and of course it would be impossible to know what Fujifilm's criteria for success might be, even if we had that information. It has always struck me since becoming aware of X Series cameras that Fuji seems to attach a great deal of value to the design proposition of Electronic Range Finder cameras. It's a pretty distinct form for modern mirrorless cameras and they might value the distinction so much that break-even or even a manageable loss on X100 and X-Pro lines is totally worth it to them.

Maybe for you or other X-Pro2 users, the X-Pro3 isn't compelling enough for an upgrade. I get that. The X-Pro2 strikes me as a great camera. In fact I decided to get the X-Pro2 and was saving my money when they introduced the 3. So I am totally into that being a thing.

For me, the X-Pro3 is a total success. I have never owned a digital or mirrorless camera before buying the X-Pro3. The details that others dismiss as gimmicks were compelling enough for me to want them. The sub monitor doesn't feel or look like a gimmick to me at all. I like it. People who ask about my camera are always surprised and delighted by that detail. They are fascinated by the fact the LCD folds down and out. I like this too. I don't want to even be tempted to chimp, but it's super nice to have a screen available that isn't smeared with skin oil when I want to double check a result or make a wait-level photo if I'm unable to crouch or kneel.

I purchased the FUJINON XF16mmF2.8 R WR as my first lens because I love the wideness. Is it a problem the viewfinder doesn't have framelines for this? It hasn't been for me. Maybe because of the way I compose things? Maybe I don't care? I certainly never once was "disappointed" or found myself wishing for those framelines. I also use adapted Pentax Takumar M42 screw mount lenses on the camera, including a Super Takumar 300mm F4. Does using this long lens make the "rangefinder" useless? Not entirely. You certainly have to trust that what you saw before you brought the camera to your eye will still be the case for the lower right of the frame. But that's where the functionality and flexibility of the ERF is so great: A simple push or pull of the viewfinder mode lever lets me see the electronic view. I can switch back and forth if I want. I can stay electronic if I want. I can have both. And I don't have to be "pure" or do one or the other. I can just do what I want.

It's not just looks, or living a rangefinder-pure life that the X-Pro3 brings, but wonderful flexibility. The instrument helps me and facilitates me.

This camera makes me want to pick up and shoot. It inspires me and instills me with confidence.

X-Pro3 a success? For me it absolutely is.

https://youpic.com/photographer/JonWhipple/