A lot of comments in defense of Apple seem to have overlooked something very important.
> If you replace the battery in the newest iPhones, a message indicating you need to service your battery appears in Settings > Battery, next to Battery Health.
This is not a warning that you are using a non-OEM part. This is an imperative for the user to get the part replaced.
Even if most non-Apple batteries are terrible, this is not a reasonable approach. IMO, it is bad for Apple to refer to anything they have not approved as defective and very misleading to the customer.
> If you replace the battery in the newest iPhones, a message indicating you need to service your battery appears in Settings > Battery, next to Battery Health.
This is not a warning that you are using a non-OEM part. This is an imperative for the user to get the part replaced.
Even if most non-Apple batteries are terrible, this is not a reasonable approach. IMO, it is bad for Apple to refer to anything they have not approved as defective and very misleading to the customer.