We don’t have to defend Linux anymore. On the servers, obviously. On the desktop:chromebook sales are increasing while Apple and Microsoft are declining. Mobile obviously. We are setting the standard for how technology will evolve in the 21st century even outside IT.
Hobbyists nowadays have much better resources and a larger peer group than in our days.
Entering a generation of open source software and hardware. More than half of the scientific papers since 2011 is openly available.
With this culture we could solve problems in medicine. You would think that by now we could use cybernetics by now, but e.g. the standard prosthetic hand is still a hook. With open source, 3d printing and open knowledge a 15 year old was able to develop an articulated arm. The way forward:collaborative development in the medical world. Same for environmental issues.