I would say that familiarity with Berserk would also be a big plus to more closely relate to the story in Bloodborne.
In my case Bloodborne was my introduction to some of HPL mythos. Ever since finishing it I was curious to get some audiobooks and definitely started appreciating more the cosmic horror genre.
So I guess it can go both ways.
I can see how bloodborne would spark that llve, yeah. Didn't think of it working im the other direction tbh, I guess I'm fixating on the terminology more than anything on reflection yet I forget people could still pick up the story through extra attentiveness without having the terms and imagery used evoke a wider understanding of lovecraft and Cosmic horror lore. It does seem a lot of people out there say BB little or no story which is so wrong it pains, haha.