There is indeed investment in France, but as your figures show not enough to prevent a net outgoing of capital.

But wealth tax is as you know now paid by corporations but by individuals. I don't get the idea of discouraging wealthy individuals from staying in France with their capital, not least since the wealth tax revenue is negligible in the big picture.

When they move or don't come to France, it's not only the wealth tax they don't pay, it's also income tax. The activity they don't generate in France or that is lost when they leave France means less employment and less taxes on salary and turnover.

If the wealth tax were beneficial for a country, it's very strange indeed that almost no one else has it.