I don't think it's accurate if you take it at face value. If you genuinely solve the world's problems, that's a better place to be (business-wise) than having solved your own problems.

But trying to solve the world's problems vs. trying to solve your own is another matter. You probably better understand your own problems.

It means: Solving your problem first > Solving others' problems (that don't affect you). The reasoning is that you are an expert in problems that affect you.

If the problem affects the whole world, including yourself, then it falls in the left bucket.