The natural order pipeline will load the value of this server parameter here to pass it to the ReshardingCloneFetcher, but the ReshardingCloneFetcher never uses this value. Previously, we would limit the number of bytes written as part of cloning to 100KiB. Now, not only are the write batches of unbounded size (default behavior of getMore with unspecified batchSize), but they are also being performed within a transaction.

This may lead to very large transactions being performed and the issues seen in HELP-70099 (but this is just speculation).