Birth rates are of course the only thing which matters. If your car runs out of gas, it will still roll for a small stretch, but it is irrelevant.

I don't know what you're saying.

>Practically the whole planet is experiencing population decline now.

That's objectively false.

It's easy to understand, how can you not understand? Any population increase is just a very short and temporary happening when births are below replacement level. Which they are in almost every country on the globe, with a few exceptions.

Yeah sure, but populations are increasing TODAY as in NOW and will happen for multiple decades for most countries.

Your statement about populations declining is just untrue.