Probably an old topic revisited... Why are my files now copying instead of quickly moving?

The same as this Post: https://discussions.apple.com/thread/4960829

Basically, I am not used to my mac asking me to authenticate the moving of any file within the same drive. In other words, once copied from computer to Drive, I could move those SAME files to any other location on the SAME drive and they would INSTANTLY move over.

Now, for some odd reason, it sometimes asks me to authenticate with my user password when moving files from the computer Local Macintosh HD over into the Ext Hard Drive granting it permission... for any copy (Which is okay, I guess for added safety.)

BUT the one that annoys me is that, when trying to move files within the SAME drive, they DON'T just instantly move anymore, instead it is as if I'm copying from computer to drive TAKING MUCH MUCH LONGER....

Even after running a First aid (permissions check) the drive is still doubling the files instead of just moving them like it used to.

The biggest issue, in my opinion is, let's say you want to organize files on the ext. drive but then realize you are almost out of memory. So the computer will not allow the move because the size of the files you want to move together, is double that of what you have available, since it is using "copy" "paste" method, instead of just moving them. So you will have to move, file by file making sure that you don't exceed the amount of your externals space.

I know I can CMD+Click+Drag to the other folder will simply move it instead of copy paste, but I didn't have to do all that before... Why now? What changed?

Why is that?