I think that guy is seriously wrong, not every hidden part of a user interface is evil. The hamburger menu tells the user that he will find the first-level navigation if he taps it.
It is about as bad as a right-click context menu on the desktop.
It is about as bad as a right-click context menu on the desktop.
Always ensure that contextual menu items are also available as menu commands.
A contextual menu is hidden by default and a user might not know it exists, so it should never be the only way to access a command.
In particular, you want to avoid using a contextual menu as the only way to access an advanced or power-user feature.