Because software video decoding of a codec that doesn't have native hardware decoding is slow (software 4K decoding taxes even many modern machines) and most im

Because software video decoding of a codec that doesn't have native hardware decoding is slow (software 4K decoding taxes even many modern machines) and most importantly is incredibly resource intensive and therefore battery draining. You've no realistic option than to support whatever formats that the hardware has native decoding support, and you'd prefer H265 over 264 (bandwidth costs money) if it's available, and there are many different HDR formats.