Supported Codec List

[TheDreadPirate]

H264 is perfectly fine still.  1080P blurays still use it.  Quite a few streaming sites still use it for older device.  But HEVC/x265 is better in terms of quality for the bit rate.  BUT a lot of browsers straight up do not support HEVC or require additional configuration or software to support HEVC, meaning transcoding is likely to occur at some point.

Since video transcoding is not an option, H264 is really the ONLY video codec choice.

Tell your friend if your videos being in H264 bothers them so much they can buy you a new server that can handle some transcoding.