Not worth it for academia means, that academia deserves something better than a vendor lock-in, by some closed-source software. It deserves a medium that doesn't stand in it's way, but empowers students/professors, scientists and other people, instead of depowering them by centralizing all power to one login provider.

Academia is about innovation and sharing knowledge. A gatekeeper or a closed-source platform inevitably creates a bottleneck that slows innovation and knowledge sharing down. Furthermore, a social network as Academia requires a medium that adapts to it's need, not the other way around, therefore an optimal solution can only be opensource.