Ford is said to be bad for discontinuing parts. Unfortunately, the parts are often the obscure stuff that's dealer-only.
A friend had the accelerator cable break on a c. 8-year-old Windstar. The part was not available from the dealer or aftermarket. Unfortunately, the local wreckers cut the cables when pulling the engines, so there were no used ones available. He had it welded, which held until they got rid of the van.
There was a CBC Marketplace story about a fairly new F-150, four or five years old and off warranty, where a piece of the HVAC system failed. The truck had no heat, and the part was not available anywhere. After the bad publicity, Ford relented and did a short production run.
I was always able to get parts for our old Mazdas - no problem getting parts for our '97 MPV as late as 2018.