It’s interesting that there is no Figma links.
They would have massive numbers of designers, all needing visual assets. If you've got a library to provide consistency to them, moving that library over to another tool is a big mission, no matter how good it is.
I think you'd find figma gets healthy use at apple, like most of the work of UI design is trying a bunch of different solutions, collaboration and feedback, prototyping - I think figma would crop up commonly for that type of work - the 'shaping' phase.
The final step of 'ok make everything look apple' isn't that big compared to everything you've done before that point, jumping tools then isn't the end of the earth.
I've done it before with the Apple Sketch files, did not have any issue.