How do you choose to watch a link? By default you get a notification when your post is linked in another post.
If this post is linked because of a watched word, like safe mode, the post owner gets a notification every time the watched word is used.
But I think the problem is not only because of watched words, it’s a problem for all posts that are frequently linked.
This feature request is similar to It should be possible to opt out of link notifications and Disable notifications for links to post.