The purpose of open source may not making money.
And maybe most of the open source developers are not good at making money.
But if there is a infrastructure to help the developers to get money through their open source software, and still keep the open source free for personal learn and use, that will be fan.
Yes, I also have the fear of losing my sight when I'm getting older.
I hope I could code even I'm 70 or 80 years old. It's not just for make living, also for dignity.
My favorite quote:
"GitHub’s largely officeless workplace — about 60 percent of its employees work remotely, using a powerful homemade chatbot, called Hubot, to collaborate."
It's really cool to work wherever you like without lose the team's efficient.