That doesn't mean that this one will become a pandemic, but it also doesn't preclude it.
Ebola also has a lower mutation rate than COVID-19, so it is unlikely to change into a more pandemic-prone strain.
I know that's not the WHO, I just cite that as an example of how the term is much more casually used than a normal person on the street might by bureacracies.
While an "emergency" is meaningful, it also isn't equal to "everyone everywhere should panic about this", it's a bureaucratic and legal term somewhat disconnected from its common definition. It triggers some provisions in some treaties and requires states to respond promptly to some things, but that's all. https://en.wikipedia.org/wiki/Public_health_emergency_of_int... shows previous ones, and COVID isn't the exemplar of their emergency declarations, it's the one that sticks out like a sore thumb.