"When I started programming, I heard a lot about how programmers are down to earth, not like those elitist folks who have uniforms involving suits and ties. You can even wear t-shirts to work!"

This alone dates the author to beginning in the eighties :D

Today, you basically must sport the "lumberjack" look to be cool :D :D :D

But seriously, yes, now as the industry matured, there is a dress code. It might vary from area to area, but it's there.