Deleting users on a board deletes all assignments to deck cards on other boards as well

Hello community,
Problem testet on: NC 25.0.12, Deck 1.8.6, NC 27.1.2, Deck 1.11.0
Initial situation: There are several shared boards. Different users are assigned to each board. Each board user has created various deck cards and some of these are assigned to multiple users. Now I create a new board and share it to some of the users that already exist on other boards and create a list with a card and assign these to users from the share. I then delete some users with assignments to the deck card I just created from the board details. The result is that these deleted users will be removed from all deck card assignments on all boards.
Can anyone understand that? Is this an intended effect or a bug?