I mean, you would effectively just see that publisher exit the horror market and then the studio, or the studio's staff if there's a closure, could pick up with a mid-tier publisher instead.
If 3-4 million doesn't cover the cost of Until Dawn, then a smaller version of the studio (or half of the studio if it's an outfit lucky enough to sign multiple projects) can try with a lower budget.
Just look at Ninja Theory for an example. They used to make $60 AAA melee action games, and that stopped working out financially, so they signed onto a bunch of small projects while self publishing Hellblade with a 20 person team, and people seemed to like the game more than any of their previous offerings.
Obsidian similarly spun up Pillars of Eternity after publishers stopped working with them, and Larian saw huge success pivoting to isometric games sold digitally instead of over the shoulder $60 games. We can look at inXile as a similar example of that.
The market is adjusting budgets. It just often happens at different publishers when a studio or genre no longer fits a AAA publisher's strategy.
Is your concern that the same publishers aren't putting out these games? Does it really matter who funded the products? I'm still not really understanding the core concern. I could be missing something obvious. The AAA publishers are more profitable than ever, and the mid-tier publishers are too, so it doesn't seem to be a real financial issue for anyone.