If there is an opt-out scheme, I cannot see this becoming that big a deal for the majority of customers and their service will likely continue working as it did

If there is an opt-out scheme, I cannot see this becoming that big a deal for the majority of customers and their service will likely continue working as it did before. (I am not saying there aren't downsides to CGNAT for consumers, but these downsides aren't likely to be noticed by the average joe)