how to delete a paragraph respecting the folds?

Question

I have a file (filetype=javascript), this is how it looks without folds:

and with folds:

I can move with the { and } motions skipping the empty lines inside the folds (thanks to these question and answer). But trying to delete a paragraph brings the problem of folds again:

My cursor is on line 1. I'm pressing d} and expecting Vim to delete the fold below completely, like on the screen shot below (as it would do, if no empty lines were in the fold):

Instead this happens (the last line of the fold has not been deleted):

If I'm doing the opposite motion to delete backwards (in this example the cursor is on the last line in the file), I'm expecting Vim to delete the previous fold (the one above), like here:

Instead this happens (the text has been deleted up to the first encountered empty line):

I looked into the docs :h 'foldopen' and haven't understood well what this means:

When a movement command is used for an operator (e.g., "dl" or "y%") this option is not used. This means the operator will include the whole closed fold. Note that vertical movements are not here, because it would make it very difficult to move onto a closed fold.

I thought that vertical motions are not supported with the operator commands, as this seemingly states, but, for instance, d3j did the job. Isn't j a vertical movement command?

Could anyone tell me, please, how and if can I use the { and } motions with operator commands, especially d? Thank you.