Copying large files in ubuntu (19.10 in my case) in Nautilus, Files or Midnight Commander and Thunar to an external drive (FAT or NTFS) gives me a box that displays the progress bar without "progression", i.e. jumps right to the end of the file size (like some sort of preallocation) and stays there showing until the copying is proceding to another file or finished. I can't judge how long the copy process will really take, nor if it is stuck or else. Is there a program or option that displays the progress "Windows"-style with real time progression and transfer speed?
You have very much memory for this to happen. Indeed, when files are copied, they are copied to a memory buffer first. From the buffer, they are copied to the disk. With respect to the applications doing the copy, the progress of committing to the buffer is what is being shown. A terminal copy command will be finished if everything is in the buffer. For a graphical program, apparently the progress dialog is terminated only when everything is committed to the disk. As a result, the progress indicator proceeds very fast but then is stalled until the full buffer has been committed.
This indeed is not very convenient, and renders the progress dialogs rather unreliable. It would require filing issues to the developers to fundamentally change the way such progress bars monitor progression of a copy or move operation.