I had heard Ford and GM had developed their 10 speed transmission for their pickups together, apparently that isn't the case. Ford developed the 10 speed for the pickups, GM developed a lighter 9 speed for FWD cars and they were supposed to "share" their respective products. With Ford basically getting out the car business (they will only have 1 FWD car built in the US) they decided to opt for the lighter and cheaper 8 speed transmission they had already sourced while continuing to share their 10 speed with GM - for now.
https://www.msn.com/en-us/autos/news/ford-refuses-to-use-gms-9-speed-automatic-transmission/ar-AAwds7T?ocid=spartandhp
https://www.msn.com/en-us/autos/news/ford-refuses-to-use-gms-9-speed-automatic-transmission/ar-AAwds7T?ocid=spartandhp