I hope Apple implements it how they already do with the Back Tap accessibility option. By giving a preset number of system / accessibility features, and then listing the user’s shortcuts library. Otherwise, it would be weirdly restrictive of them.
I think you’re misunderstanding their point. They’re saying they don’t care about another ad-filled, user tracking social media platform (Threads), which is inherently opposite to what Lemmy is. They and myself care enough to not see the influence of Threads / Meta on Lemmy, and the Fediverse as a whole.