Maybe because it is something HN readers worry about. Seems like a pretty reasonable explanation...

Because complaining is easy, and earns you social kudos. Doing something is much harder.

If someone makes this device and markets it 5 years from now, Reg can point back to his blog post and say "See, look how smart I am"

There's a normal human tendency to occasionally worry about whether one is doing the correct thing with one's life. And then sometimes people extend that from themselves to those they associate with.