Tell us you didn't read the article without saying that. Plus even if they had used normal paint, that's literally nothing compared to what this yacht does on a regular basis.
They got their message on international news, and they did it targeting the super wealthy instead of blocking traffic or otherwise hindering innocent people. Frankly I don't care if the crew has a 'headache' being paid to clean up some biodegradable paint, they're just being paid for one task instead of another. What actual harm of any kind has this done? The benefit might be small but it's nonzero unlike what most of us are doing.
There's a lot of money pushing this idea. I live in a certain US state where an organization has been paying to have billboards up that push this idea for years now.