Yikes, I can remember when turn of the century meant something different to what it does today.
Meh - I'd say the previous one was much more important. Napoleon upending Europe's political & social order, similar in China as the Qing put down the White Lotus Rebellion, Volta inventing the electric battery, ...
(;
My wife's student asked: "Is it ok if I quote a few papers from the end of the last century?"
Made me feel very old indeed!