Honestly, for network code it makes more sense when the data is received to add the time to the current era. A 64 bit timestamp is an extra 4 bytes of overhead.

Honestly, for network code it makes more sense when the data is received to add the time to the current era. A 64 bit timestamp is an extra 4 bytes of overhead. However, the biggest issue with a network protocol is you just can't force everyone to update everything. Now it's some in house protocol sure you can just update everything instead making the timestamp a relative value to the current era. For code running locally 64 bits is less of issue, just mainly a problem of ABI breaks. Honestly, one thing I think people overlook is file-formats... A lot them have 32 bit time fields. Also unlike a network packet the file could actually be from a previous 32 bit era. So those timestamps are ambiguous after 2038.