I thought this was limited to the CX-50 only, and I had assumed that it was a cost-saving measure from the Alabama plant.
The CX-90 doesn't seem to have this issue, and the artisan red paint in the door jambs looks the same as the exterior. The engine bay has the same colour, but doesn't have the high gloss clearcoat that the rest of the car has, which is to be expected. Thus, there is no reason to jump to the conclusion that all Mazdas going forward will have this difference in colour in the door jambs.