Is the Aberdeen Act JE broken?

Maybe I missed something, this is my first time playing as Great Britain so I have no idea if it was always like this. But I've been kindly demanding that Brazil ban slavery for 45 years, and they keep saying "yeah, we'll get around to it" and avoiding war, but literally nothing happens. Since Ban Slavery used to function like Open Market, immediately inacting the relevant policy, is it broken in the current games? I'm about to just steamroll them out of frustration, but I still have no clue how to actually force them to ban slavery. What am I missing?

As a side note, Britain is surprisingly fun to play as, at least for this go around. There is so much stuff going on with all the colonies and interests and rising powers that it isn't boring as I expected for some reason. If you've been avoiding "starting in first place", give it a go!