Having spent the last three days trying to work around some pretty subtle and nasty bugs in both the new and classic FolderItem classes I decided to write my own module for robustly handling file/folder moving/copying/deleting. The module is essentially a nice wrapper around the cp and mv commands on Unix systems and the move and xcopy commands on Windows. The source code is available on GitHub, as is extensive documentation.
I couldn’t reproduce them reliably but I was seeing repeated failures on Windows 10 with the Xojo.IO.FolderItem.MoveTo and Xojo.IO.FolderItem.CopyTo methods whereby I would get odd errors and failures stating that either destinations were not empty when they should have been (and were) and inexplicable permission errors which just melted away when I used the Shell.
nothing from the new framework is deprecated as of yet. The announcement at XDC that they are migrating back to the oldframework was a its going to happen one day, not today type of announcement. And I predict that they (Xojo) will merge the good of the new framework with the oldframework. to make a better framework. But nothing is happening overnight. Plus when they do mark something as deprecated, it takes a good long while before it is removed (saying a year is a short interval).