This is personal income tax, for physical people living in the country. Investors don't need to take actual residence in France to invest in this or that company, so that's not really going to change anything. Any celebrity worth that money is already living in Monaco (or similar tax haven). The only people affected by this are millionaires who, for some specific reason, are forced to live in France: footballers and very few others. Hence why revenue projections are actually quite low.