It's not the parts that are locked, it's the phone that wants specific parts. If you give people the possibility to change their phones to accept other parts yo

It's not the parts that are locked, it's the phone that wants specific parts. If you give people the possibility to change their phones to accept other parts you instantly create a market for stolen parts. Maybe Apple should lock both sides. Another reason for locking parts to the phone is to prevent non-genuine parts. Those cheap batteries or TFT replacement screens for OLED iPhones will not give the experience Apple intended and will damage their reputation.