Command + D is making copies of files, not deleting them

As Niel said, you want Command-Delete

and not Command-D.

Incidentally, this has NOT changed with Monterey, it has been like this for many years. Could you post a link to those instructions you found that mention Command-D?

Do come back to the Apple Support Communities ( ASC )  in the future, if / or when additional questions may arise.

There are many Contributors who maybe able to answer these additional questions and offer more advise when needed.

Now I am wondering why under Edit in the menu bar, the item Delete is so often gray/not accessible and even disappears when a selection is made.

In what app are you seeing a Delete command? There isn't one in Finder, but I imagine I made an assumption about what you are trying to delete.

Predicated on the file or folder is Already in the Trash ( Bin ) - Right click the Trash (Bin ) and choose pop up the sub menu

refer to below

This is intentional. Press Delete instead of D.

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