I don’t agree with your statement that the “key to the discussion...” is that we can choose to follow God or not.
All would agree that no human follows Jesus 100% of the time because we are sinners. Protestants accept that and don’t believe it has an impact on a believer’s salvation, because Jesus paid the penalty for sins once and for all. Are you implying that if a person chooses a path that is not following God just once when they have been faithful all other times then they don’t have a saving faith??? If so, that would include the whole world.
The Bible is clear: God gives us a choice.
Make of that what you will ... I tire of the argument, which is quite literally pointless.