I cannot say if ACF plans to go down this path or not, I am not the developer and you would have to ask them directly.
However, they would not be the first plugin to use this model. Perfect example is Elementor Pro. If your license expires, any pro element already in use will continue to work but you cannot edit them or add new pro elements.
It would not surprise me at all that they choose to do this simply because currently it is possible, if you want to do the work, to have ACF Pro installed on multiple sites without needing a license for multiples sites because of the way it currently works. This model would eliminate this possibility.
