Memento mori is a caution against excessive pride. We are all equal in the grave and we are all going to die. Memento mori tokens or reminders were carried by powerful people to remind them to temper their decisions and maintain humility. Definitely not the “fuck it” attitude of YOLO.

I think the similarity comes from the literal meaning of the two but doesn’t extend beyond that. “Memento Mori” carries a distinctly humble meaning related to the concept of “vanitas”, the idea that death is inevitable, even for the rich and powerful, and that earthly pleasures are vain and meaningless. That’s really in the opposite direction of YOLO.

Bruh the comment section is basically a highschool circlejerk

Morituri te salutamus

We who are about to be YOLOed salute you.

Standard greeting of aspiring YouTube extreme video channels.