the tax/financial/debt burden

What does that mean?I want to know how we use it in conversation?
It's not often that this comes up in conversation unless you are specifically talking about finance, taxes, etc.

It's all money talk.

Have you seen a specific use that you have questions about?
It means: How much do you owe; how much debt you have? Debt is considered a financial burden. It is used when you are talking business.