Its the bare minimum required. Birth rates should be above replacement rate. Currently they are not. I'm in favour of raising birthrates for many reasons but i think the contention is on the sustainability aspect which is why I choose to point out that most countries are currently in a position to sustainably increase their population.

If you want to argue that china/Nigeria/india should not have an increasing birth rate then I'd agree because that is not currently sustainable. Unsustainable population growth forces war or famine. At the moment china can trade for food but the moment something changes and they can't they are forced to make a choice. The generally increasing birth rates are from countries that can't sustain themselves. I dont think they should have as high of a birth rate as they currently do.

I'm in favour overall world birthrates increasing but it should be growing throughout the world sustainably instead of booming in the poorest most resource starved places.

I dont care for the panic of different ethnicities within a country. I think once the overall conditions improve to where the birthrates raise all the ethnicities I'm that country will roughly balance out to similar birthrates and they will mix anyway.

I dont think any of that id crazy or shocking rationale.