Someone will collect the lead for scrap, it's valuable enough that even in wealthy countries it is worth stealing.

I take it you've never taken AP Chem.

Here's how you extract lead from lead acid batteries in the developing world (video is from Pakistan, but same principle in India, Vietnam, Phillipines, etc) [0], because Western Europe level environmental and labor laws aren't a thing.

[0] - https://m.youtube.com/watch?v=kNGg0P7B5fI

So what's the problem? The battery is clearly recycled, it's not going to end up in a river, burned or in landfill.

That's great and all, but lead is nasty stuff. I really hope it's use will diminish. Lead handling is always fraught with risks at every turn.