You should at least read the list before making assumptions. The official suppliers list clearly differentiates between PRC (381) and Taiwan (67). From cursory

You should at least read the list before making assumptions. The official suppliers list clearly differentiates between PRC (381) and Taiwan (67). From cursory reading, China supplies more materials and components than all other country combined. Some of it is lower tech and can be replaced, but not all of it and certainly not in the short term. Edit: To add, China's strength is both logistics and the ability to setup new production processes. Mature processes for old phones can be moved to India for production, but major hardware changes in new sku is still only viable in China because only China has the expertise, logistics, capacity to rapidly iterate and trouble shoot new products.