[BIP Draft] Segregated Data: a prunable, script-isolated block region for data carriage

The synchronization process for new blocks beyond the tip in a node does not necessitate the SegData extended serialization of the block. Instead, it relies on the base serialization which excludes any data payload, ensuring both completeness and blockchain consistency. This protocol is thoroughly outlined in the peer services bip and further elaborates on block construction methodologies.

Furthermore, the SegData component, while not essential for initial block download or validation processes, can be reconstructed and requested through peers that synchronize SegData. This allows for additional validation by rehashing entries to confirm the accuracy of reference hashes. Importantly, this process adheres to current standards regarding block size and transaction weight, without necessitating an increase in block size limits. It operates under a principle similar to 'assumevalid', but specifically applies to the data portion of the block.