I've found that volunteer work is _harder_ in terms of getting the human aspect right.
New volunteers sometimes expect the red-carpet treatment as someone volunteering their (pretty expensive presumably!) time and as someone accomplished in their field. Volunteers usually get the opposite treatment since it turns out the other volunteers tend to come from a similar perspective and someone doing the hard human work is often contributing a lot more to the project than an otherwise excellent engineer.
You can of course choose your volunteer activities to be interesting to you. Open source is one such very fun activity but lo-and-behold in projects I've been involved with the human aspect is often very important and requires a similar amount of hard work. This is often truer for bigger projects/organizations than small ones.
Even if you're volunteering you still have to work towards agreed upon objectives. You wouldn't show up on a Habitat for Humanity build site an start modifying the blueprints and working on whatever you found interesting because you are volunteering and are entitled to only work on interesting projects.
But having people working on potentially extremely useful moonshots that they are interested in for free is a huge win. I think it's really just a case of bad advice, and not all developers with 40+ years of experience are correct. In my opinion, it's better to have a motivated volunteer engaged and working on something with unknown impact that she is interested in, rather than get her to work on boring things with less impact.
of course not, humans are most often wrong about everything. Someone with experience is just that. Our perspective changes.
I started coding at 12 because everyone said it was much to hard for me. Now im old and motivate people by doing the same. At the same time its good to be reminded by others what happens if you drop one thing in favor of the other.
