I don’t think I’ve heard of a toll being reduced in decades. I only know of one toll that was actually eliminated. Normally the ‘tollway authorities’ are dead set against that ever happening again.
The Hogan administration in Maryland reduced tolls for EZ-Pass users in passenger vehicles shortly after assuming the governor’s mansion.
Toll eliminations that I know of:
Dallas-Fort Worth Turnpike (I-30)
Richmond-Petersburg Turnpike (I-95/85)
Ga. 400 in the Atlanta Metro
Ramp tolls on the Kennedy Highway and Delaware Turnpike (I-95)
I-95 bridge in Jacksonville, FL north of downtown
I think that pretty much exhausts it, however, since hardly anybody wants to remove tolls, even if they promised just that.