Verizon's legacy wireline business is regulated and publicly funded via USF. They cannot just force people onto FiOS abandon the copper.
Actually, they can, unless the FCC reverses itself.
But revisiting forbearance would not solve anything. The problem is the underlying cost of FTTH - a price most consumers are unwilling to pay. Re-regulating telco would result in higher, not lower prices overall.
They could force you over to FiOS. AT&T did this in areas where they built out FTTH under Project Lightspeed. and only the dial-tone is regulated, not the Internet. They could also pull an AT&T and go to each state and ask them to de-regulate their business and remove MTS if the customer bundles- which states are doing for AT&T.