Of course, I realize he's talking about defining events that delimit major changes between the previous century and its successor. And more specifically, major changes in what Thiel cares about, like financial markets, start-ups, monopolies, and money in general.
But, really, we're only 20% into the century. Something else could easily eclipse Covid-19 even within the parameters of what matters to Thiel. You know, like climate change, the second coming, asteroid hitting the Earth, quantum computing, "the singularity", etc... Who the F knows? There's no utility in this kind of thinking. Just take it for it is and what it becomes since starting on Jan 1st, 2000.