This sounds made up tbh. I mean, I agree it's common to feel this "pressure" but the day you discover the pressure isn't real is the day you level up. And I charge plenty for fixing peoples' software pains.
I do open-source and write blog posts to satisfy my own desire to publicize my work, and for exposure, and to put my skills on display. Not as a race to the bottom. I could have had a career without those things.
Devs are expected to contribute to FOSS, write free educational blog posts about technology, and fix your friends computer!
Ask a doctor why something hurts and they tell you to come into their office and insurance will bill you.