I understand your point and was responding directly. That is, I don't think you're point is supported.

The cutoff is far above what she makes. For her to pay anything significant she'd have to have a net worth well above $100m.

She also justifies the $50m explicitly. That is roughly the percentile where 0.1% of people would be affected. The other cutoff (where the tax goes up to 3%) is at $1b. That is where 0.05% of people are affected.