If they could just sidechain as Layer 2 bitcoin, but no. Sunk cost has them good. A deep analysis of XMR shows it's far worse at scaling than bitcoin, and inevitably centralizes nodes.
As an L2 though, borderline necessary. Privacy doesn't get enough attention by bitcoiners, and if we can't soft-fork a means to break chain analysis safely, L2 Monero is the next best thing.