Thank you for tracking that down. My main point was that Bunkus had made up his mind that although his decision to use V_QUICKTIME was causing confusion, he was sticking with it. The codeberg.org message was the one I was referring to when it was back at Gitlab.
As for the help.mkvtoolnix.download message, which I was aware of by doing a search on V_QUICKTIME in that forum, it shows the importance of using the latest versions of the “programs under the hood” (as someone referred to it as). For reasons unknown, the developer has chosen to not do timely updates to these programs. The worst offended being using proprietary YoutubeToMP3Process.exe instead of the latest stable or nightly yt-dlp. It’s annoying to see SF problems already fixed in the latest versions of yt-dlp, but not when using YoutubeToMP3Process. Note: when I mention YoutubeToMP3Process, I also mean to include YoutubeToMP3Service, although I’m not totally sure of the relationship between the two other than the implied use of YoutubeToMP3Service as a service.