Update on what I think of the processes so far...
Let me state why I would like to be able to de-select Dolby Vision when making a movie-only copy. I should add that MKVToolNix does allow Dolby Vision to be de-selected when making an MKV. But of course that does not help if you want to make a BDMV-formatted disk.
I should also note that HDR10+ is a whole different story. Dolby Vision is a separate video track. Dolby Vision shows up as a separate track in the BDInfo files created by DVDFab, and it shows up as a separate video track in MKVToolNix, which is why you can de-select it. But HDR10+ is not a separate video track, so de-selecting that may not be possible. Dolby Vision and HDR10+ may be fulfilling the same basic purpose, but the manner in which they do so are completely different animals, so please don't confuse the two and think that they could be treated in the same manner.
Back to why I would want to be able to de-select Dolby Vision:
1. When compressing a UHD to fit on a BD50 disk, the Dolby Vision track is not compressed, resulting in greater compression of the main video. If your player or TV does not support Dolby Vision, you are losing quality as a result. Sometimes removing Dolby Vision might even be sufficient to get a movie to fit on a BD50 without compressing it.
2. UHD disks with Dolby Vision, when compressed to BD50 size, have significantly less playback compatibility even on players that do support Dolby Vision. For example, I have a number of such disks that will not play back smoothly on my friends Oppo (which supports Dolby Vision) but will play back smoothly on my Samsung UHD player (which does not support Dolby Vision so the DV track is ignored).
Since DV is a separate track, and MKVToolNix allows you to de-select that track, it would seem very possible technically to have this capability added to DVDFab.
I hope this explains what I am requesting a bit better.
Thanks for any feedback Mona.;)