This is a really good example of how capitalism doesn't work so well in a digital economy. Normally there is are various arguments about how the subscription pays for the development / invitation. But here we have a feature that's been there for more than a decade, the only innovation is figuring how to monetize it.

Isn't this because it's not a free market, e.g. the DMCA and other laws that prevent publishing how to work around digital locks?