If you’re unfamiliar, “five nanometer” is shorthand for how small the transistors are on the chip itself, and it’s a process not everyone is using right now. Apple proudly boasted that it had the world’s first 5nm chip, the A14, which was made by manufacturing partner TSMC. It’s the same process that Huawei used to build the Kirin 9000, before sanctions made that unavailable.
Samsung’s production of a 5nm chip means that TSMC no longer holds the monopoly on the process, and hopefully we’ll see more efficient chips from all phone makers in future. After all, the smaller your transistors, the faster, or more power-efficient your phone becomes. And that’s a big deal right now, when the switch to 5G is emptying people’s phone batteries out faster than ever before.