You’re focusing on the wrong part of my argument. The cat bit was a humorous throwaway.

Memento mori is directly and explicitly tied to humility and mindfulness. This is well documented from both contemporary and historical sources and is absolutely distinct from the indulgence of “making the most out of life”. YOLO is about risks and embracing the experience rather than contemplating the consequences. YOLO is closer to “hold my beer” than anything else.