What do you think that proves? Yes, it does lower your tax bill to give away gains before they're realized. That's because you do not realize your gains. That's called simply "choosing to earn less money."

Tax dodge would imply the purpose is to reduce your tax bill and still see the upside. There's literally no evidence of that. All the upside he/his family sees will continue to be taxed at the normal rate.

If you're Yvon Chouinard, whose goal is to keep Patagonia going in perpetuity as a funding vehicle for environmental activism, what else could you do?

For the record: he divided up the shares into voting and non-voting. He "donated" the dividend-earning shares into a 501c4 foundation whose mission is to invest in grass-roots environmental activism, and "donated" the voting-power shares into a separate trust, whose objectives are to ensure that Patagonia continues on the path he gave as an example for the previous decades and to hold the 501c4 accountable.

The boards of these organizations are composed of the people whom he most trusts to fulfill his vision, a group of people that includes his children.

Knowing the full context of their lives, it's hard to see it as anything other than one of the more simple solutions to a complicated problem.