Breaking change in calculation of hash_serialized_2

The email discusses the topic of considering an option that was not previously discussed. The sender mentions that they couldn't find any reference to it in the original proposal and also states that they cannot recall it being discussed since they started following the project closely in 2020. The reasons for this could be:

1. The serialization and hashing of the UTXO (Unspent Transaction Output) set is assumed to be working well, so there may have been a view that adding another hash would be unnecessary overhead. The hash_serialized_2 has been considered robust for a long time.

2. There might be a desire to optimize the serialization of data to file further, potentially introducing compression techniques to create smaller files. This would allow for the same UTXO set without changing the chainparams committed to that set or having multiple file hashes for the same block.

3. Alternative file hashing strategies may be explored, specifically ones that are more optimized for peer-to-peer sharing of the UTXO snapshots. While P2P sharing of the UTXO set has always been part of the assumeutxo idea, it hasn't been deeply explored yet.

The email references a conversation on IRC (Internet Relay Chat) that took place in a meeting yesterday between sipa, aj, and others. More information on this can be found in the provided links [2][3].