Yea, its fundamentally an issue of asymmetric economics.

Running AI scanners internally costs money, dev time, and management buy in to actually fix the mountain of tech debt the scanners uncover. As you said there is no incentive for that

But for bad actors the cost of pointing an LLM at an exposed endpoint or reverse engineered binary has dropped to near zero. The attackers tooling just got exponentially cheaper and faster, while the enterprise defenders budget remained at zero.