Just due to unable to buy by everyone, we cannot assume that bitcoin is a bubble. Even with the price tag of $64k, some one who has only $100 can invest with bitcoins and may enjoy 10x to 100x profits by holding it. I mean not everyone needs to buy one full bitcoin but they can buy fraction of bitcoins as per their affordable levels. So, calling a bubble due to huge price level is completely meaningless in my opinion.

The current price level may seem huge in your eyes but when bitcoin will be having higher value than today's price then you will understand how wrong you are on assuming and calling it a bubble. Because, people called bitcoin a bubble when it was reaching $1k for the first time but right now it is trading 60x higher than that.