Just to clarify (and pile on more pedantry?): it's a JS feature that is also implemented by TS, so while you're correct that it's not a TS feature, it's also no

Just to clarify (and pile on more pedantry?): it's a JS feature that is also implemented by TS, so while you're correct that it's not a TS feature, it's also not particular to Babel. In fact, sometimes I like to use TS because it allows me to skip the Babel part of the process entirely.