Note that we unfortunately can't use a scripted diff here, as the same
property name is also used for `CBlockHeader`/`CBlock` instances.
This is a partial backport of [[https://github.com/bitcoin/bitcoin/pull/32421 | core#32421]]
https://github.com/bitcoin/bitcoin/pull/32421/commits/81af4334e8f903601dac503426eaccc1d3527f9c
Depends on D18714