Really? Being upset about this is like being upset about Thor and Loki being in the MCU. All gods are made up. It just so happens that Norse, Egyptian, Greek and sometimes Celtic gods get to live on in the popular imagination while countless others are nearly forgotten.I'm also not a fan of real world mythologies in fantasy worlds, and would rather we got new gods of the north, rather than the Norse pantheon.
And just to be clear: I feel exactly the same about currently broadly invoked religions. Give me stats for Samson.
Anyway, "Norse but serial numbers filed off" religions are orders of magnitude more insufferable than just saying Thor.