stunning yes, but you can get ascii generators to do simular works. He even mentioned at the top that it is "rendered" images.
There's ascii to art, pic2html, ascii studio, and many online converters if you look for "Ascii art generators". Ascii has been around for over 15 years that I know of - possibly more. Still most of the ascii art is random characters, This person found a program that does phrases with multi-scaled font size and he's not sharing the link. His images are very cool.
If you are neutral in situations of injustice, you have chosen the side of the oppressor. If an elephant has its foot on the tail of a mouse and you say that you are neutral, the mouse will not appreciate your neutrality. - Bishop Desmond Tutu