A somewhat condescending phrase used when responding to an often ridiculous, silly, or funny statement. It is used to denote to the person who said the statement and can probably be likened to saying "Tsk, tsk" or "Oh brother."
Often a person will shake their head, laugh, or point when saying it.
When finance content creators rent out fancy cars and flexcash to seem richer than they really are in order to promote and sell their “get rich quick” courses.