Tameem Antoniades, the creative director of Hellblade: Senua's Sacrifice, has always said that he knew the game's "strangeness" and focus on mental health issues would have consequences for the game's reception and sales. We definitely think the game has a few issues, but that it's still something worth experiencing. That's why we're glad to learn that Senua's story is doing better than expected.
Ninja Theory has announced that the game is closing in on half a million copies sold and that they've reached break even. They've also released the game's 30th developer diary to celebrate this, and it's definitely worth checking out. In it, the developers reiterate their concerns before launch, some of the controversies at launch, how glad they were to see people embrace the game, and even share a few details about how they managed to create such an impressive game with a relatively small budget and team (with a few references to the recent studio closures).
Congratulations, Ninja Theory. We hope the game continues to do well and that you keep experimenting. It makes for some very interesting experiences for players and thought provoking ideas for developers and publishers.