When people agree on something, it forms a bond.

That bond brings them together... but might also put them in a deeper intellectual rut together.

An intellectual rut is where you might not notice disconfirming evidence because you're too deeply tied to a given view.

Unless it's a highly relevant topic that they care about deeply or affects their day to day, a subordinate would all else equal rather bond with their management chain.

This slight edge to sharing confirming evidence can self-strengthen the more that it happens.

The one person who cuts against the grain to share disconfirming evidence will have to stick their neck out even further.

This can lead to emergently-manufactured confirmation bias that decoheres from ground truth... even if everyone is well-intentioned!