Mr Edwards said Cadw, the body in charge of safeguarding Wales' architectural heritage, did too little to protect the buildings, which he said are defining symbols of Welsh nationhood.
Writing in Viewpoint, the newsletter of the National Churches Trust, the Welsh journalist said Cadw gave greater prominence to "countless castles, fortresses, and monuments of importance" at the expense of chapels - few of which are given Grade I-listed protection.
"It really is no exaggeration to say that the spirit of the chapels shaped modern Wales - but modern Wales doesn't want to know," he said.