It has been observed that with chained replication disabled when the current primary becomes unresponsive and the secondaries elect a new primary, they keep syncing to the original primary for a notable amount of time instead of switching to the new one as soon as it is transitioned into PRIMARY. It causes the following issues:

• The new primary will fail to acknowledge w:2+ writes since there are no secondaries syncing from it, effectively making the outage longer
• If the original primary gets unblocked, there is likely to be a rollback not only on that primary but also on the secondaries.
• The rollback can happen on a majority of the replica set members

I would be better if the secondaries could re-evaluate their sync source immediately after the new primary becomes available for writes.