[papertyger]

This is a common misconception by Catholics as they think equate it with some “private interpretation unauthorized by Scripture, contradictory to Scripture and unverifiable” which is patent nonsense.

Then why is there no universally accepted Protestant doctrine of Baptism?

[JLLH]

Because it is only symbolic and regeneration does not hinge upon it. Most follow Christ’s example (again, found in Scripture, which Catholicism loves to pretend it invented.)