Just woke up and thought this would be one of those topics. Turns out @EA_Barry just cleaned the whole house 😂
It is one of those things we should recheck for risk of practically creating a metonymy for ourselves, mixing up cause and effect.
Differentials were made to allow the wheels to spin at different rates, as the alternative would be a solid axle with a single turning rate forcing one wheel to spin in place or to drag behind when maintaining the same wheel speed is not possible.
The main use case is cornering, yes, but it's actually whenever the spinning rates differ.
Kevin Magnussen released a book after being booted out of the F1 circus, don't know if it's available in English already but the media picked it up. There's a part where he goes like whatever, I'm not coming back to F1 anyway, so here's my race start procedure - and he goes on to mention how he would always open his differential and how he found it odd that people didn't talk about it that much.