What do people even mean by "Authentic" Japanese, etc?

Like honest question, what do people mean they want something "authentic" food, stuff, etc.

Am I just that simple of a person where if I just eat like literally the most normal ramen in Tokyo and just be happy with it or like just buying simple stuff in Tokyo not authentic enough? I stayed in a ryokan before and it was very nice and simple, got food, tatami mats, hot springs and I thought it was fun experience.