There is only zero incentive if the filter detects AI music reliably. It's still a race between effective detection and cost to generate content, isn't it?

Why would someone doing that voluntarily tag their content as AI? they can make money by hiding it.

Unless they directly embed promotions in it. I could see this being an avenue for brand-derived fake artists. I wonder if they already have a policy for that and I wonder why it wouldn’t apply to, say, the beastie boys talking about adidas.

They say only wholly produced music using AI can't be monetized, nothing stopping it's 95% AI and 5% Human. Also no concerete definitions of what that even means.

It won't be monetized until they create a new monetization policy where they get a greater revenue share from it.