At the risk of sounding overly negative, these things are pretty much always vanity projects. Someone wanted a really cool boat and managed to get some investors onboard. It’s more about an aesthetic than a business case.

We’re talking here about a fairly large crew that will transport a small amount of cargo while taking a really long time. On top of that, these aren’t container ship so loading/unloading will take a long time. There is no economic case here.

The only way you can make this somewhat work is by selling the aesthetic/story. E.g.: this coffee was shipped by sailboat. But even then, notice how every company linked in the article of another commenter aren’t actually operating anymore…