This isn’t necessarily true. LEDs are capable of running for years, but not all LEDs are designed this way or are operated this way. An LED in a given application can die quicker if:
the LED manufacturer cheaps out
the phone manufacturer runs the LED at higher current for more brightness
the phone is poorly designed, allowing the LED to heat up
the phone is exposed to significant heat and/or the LED is covered while used for a long enough duration
LEDs should last for tens of thousands of hours. There may have been a manufacturing defect in OP’s case.
This isn’t necessarily true. LEDs are capable of running for years, but not all LEDs are designed this way or are operated this way. An LED in a given application can die quicker if: