It was tough to find (it's odd that Ford is so subtle about this) but it is listed here: https://www.ford.com/trucks/f150/f150-lightning/models/f150-... ("dual electric motors, one for each axle"). They were so busy 'materializing' their specs pages they forgot to mention this feature anywhere afaict - I had to search on their site to find the above page.
Thank you. 4x4 is also a "preference" checkbox on the quote tool, which makes me think it is not standard, and it calls out RWD drive all on the models on the main page (but in a vague way where it's not even clear that 4x4 is available).
Unless I'm reading Ford's website wrong, 4x4 is not included at the $50k price... but I'd be happy to be wrong because that would be good value.