It increases risky behavior because it’s now assumed to be less dangers that I’m not convinced a generator mounted cut off will fully mitigate. Also it increases costs and presumably false shutoffs due to stagnant outside air conditions or similar when the sensor cuts off.

I could easily see a person now choosing to run an indoor generator and relying on the cutoff to trigger when the levels are too high. In a hurricane situation I could even see taking that risk myself under desperate circumstances.