I want to reply to this, because MTP issues still exist with the current version (I'm on the beta 12.10.4).
MTP is unusable on DOPUS. I have reported this before for 11.0 and 12.0. File copies freeze almost always, but don't on normal File Explorer. Once it's frozen on the copy, it will not respond. I even have tried leaving it running overnight. The only thing that fixes it is unplugging the device, which leaves DOpus in a crashed state which is not caught by the program, so I have to force close it from Task Manager. I think there are more issues in DOpus related to MTP than Explorer, contrary to what you think. This is really annoying because I have always been forced to use File Explorer for MTP operations. I have not wanted to report recently, because I have believed it to be due to Windows System corruption. But 2 weeks ago I completely fresh installed my PC with a fresh USB install (Downloaded using a clean device). Issues still persist. I have confirmed this on multiple hardware configurations, even with different chipsets, processors, RAM, and GPU's. I have also had this issue with multiple phones and my media player which uses MTP.
As far as I can tell, it seems to freeze once the MTP device goes on standby. File Explorer continues to copy, but when my phone's screen turns off is when I often see the freeze happen in DOpus. It also happens to DOpus when multiple operations are being handled at once like opening a folder while files are copying. This does not happen in File Explorer.