Why eac3to and not something like MakeMKV? Yes, MakeMKV is really easy to use because it’s basically a one-click program. However, it does have its shortcomings when it comes to detecting and correcting authoring errors on Bluray discs.
Take that for what you will I guess. They didn’t elaborate at all.
If you’re interested in using a command line tool to demux, you can get it here, at the original thread on doom9.