Toggle tasks visiblity board independendly

I am unable to find this option or it just doesn't exist. Eitherway, it would come quite handy to turn off the visibility inside tasks for several board. Some oards are maybe not meant to get done any time soon, because they're more like a persistent library ( sorry to everyone if this is not the intended way of using deck, but i am glad Deck exists). Then it actually not usefull for them to show up inside tasks where I am also unable to find such an option. So it shows up in the "All" section..

There is "Turn off die date reminders", but there should also be "Turn off tasks/calendar visibility".

Edit:

Eventually, but this might be too explicit, it might be even usefull to "mute" individual lists
One could just create a new Board with desired Tasks, if "only" boards could get this feature, but because you can't intuitively "drag'n drop" between boards, this is not a time-consumption-minimizer option in some cases. #3478

Because inside Tasks you neither can delete Deck lists, nor can you set a Deck List as the Default List. Only Calendar created via the calendar app can be used as the default.

I dont know if its on Decks or Tasks side why its not possible to create new Tasks via Tasks... I dont get this crossover. #1878

Start by reviewing the related context in issues #3478 and #1878, along with the Deck/Tasks crossover described here. Clarify whether the intended scope is board-level or list-level muting, then verify the chosen visibility behavior across Tasks and Calendar.