It's even funnier because the guy is mocking DHH. You know, the creator of Ruby on Rails. Which 37signals obviously uses.

I know from experience that a) Rails is a very junior developer friendly framework, yet incredibly powerful, and b) all Rails apps are colossal machines with a lot of moving parts. So when the scared juniors look at the apps for the first time, the senior Rails devs are like "Eh, don't worry about it, most of the complex stuff is happening on the background, the only way to break it if you genuinely have no idea what you're doing and screw things up on purpose." Which leads to point c) using AI coding with Rails codebases is usually like pulling open the side door of this gargantuan machine and dropping in a sack of wrenches in the gears.