It does not, but usually topics are unpinned because the user read the topic and then the topic is automatically unpinned.
I think most users don’t unpin the topic using the button. It just happens.
Hiding the button isn’t enough to prevent it either as you can also click the pin icon in front of the title and you probably don’t want to hide that and even then there is the keyboard shortcut for unpinning.
I would try changing the default first and see how that goes