It is just a reminder that an item that you have watchlisted is actually already available. Which may be a welcome thing, if it’s a title that you have put on a wishlist and intended to wait until you can watch it.
In this case, this hub may also include any servers which are either your own, or which are shared with you.
Did you click on it and verify where it is available?
Well I know it’s already available to me as I have this series that ended several years ago on one of my servers. Sure maybe it’s helpful to know that potentially a new season is available elsewhere if it’s an ongoing series but I don’t need to know that if I already own it, do I?
My main complaint is that it I find it distracting to see that inserted where it is. To me it makes more sense to know what recently aired which is now hidden from sight because of that.