I don't see "meaningful" as referring to something like helping the poor, I see it as referring to feeling fulfilled. If that involves helping the poor, more power to you. Me, I took a $20k paycut to switch from writing node js all day to pen testing at another firm and I could not be happier. It's been two years since switching and I still look forward to waking up and going to work each day instead of groaning and dying a little on the inside. Paying $20k/year to be happy and feel fulfilled is a complete steal in my book.

Just my own anecdata though.