Show me a case where a toll highway, tunnel, or bridge is converted to a free thoroughfare. It never happens.
Incidentally, toll hikes were never contemplated in the original plan to build the Holland Tunnel, as tolls were to be rescinded after the initial costs of building the tunnel were recouped. But by the time this recoupment was close, PANYNJ had taken over the tunnel, and needed further financing for the construction of all the other Hudson River Crossings named after engineers (Goethels, Outerbridge) or presidents (Lincoln, Washington). PANYNJ is entirely non-profit, as it runs according to an interstate compact negotiated between New York and New Jersey. For PANYNJ to raise capital, it issues bonds, approved by the two states, which are backed by PANYNJ’s toll and rental income. Long story short, when PANYNJ needs financing, they raise tolls.