People can and do change their minds.
I can see that Gregory is a person who has changed his mind in the past when he became convinced that certain things are correct.
I pray he does not become too hardened in this current error he holds.
One has to be open to truth. Clearly some people aren't -- at least not at present.
In my experience once people fall into the Feeneyite errors/heresies it has a very unsalutary effect in them.
It is interesting to witness the effects of a modern-day, contemporary heresy.
Of course it also very saddening to see the tragic still unfolding outcome of it. One can see how widespread the effects have become. The ramifactions are enormous. Witnessing this allows a better understanding of Church History, and how it took centuries sometimes for heresies to be wiped out, only to see them resurface sometimes, in some cases with new slants or variations in order for Satan to more easily deceive the elect.