In a weird way, this would be a regressive policy -- the data of the richest people is worth orders of magnitude more, so this would just make the rich, well, richer. Increasing corporate tax rates would help the poor much more.
This sounds wrong. The value of data is in the massive amount of datapoints. If I had a data company I would always pick the large masses and discard the outliers if given the choice.
If you want to target ads, which is where the majority of the money in 'data' comes from, personal data about rich people that helps target ads to them is a lot more valuable than personal data about poor people.
Really depends how you measure the value of data. Rich people being served ads is more valuable, but the targeting algorithms probably churn on all the data at large. I imagine given Yang's history he'd argue for the latter and cut a flat fee to everyone like they do in Alaska for oil.