But that's my point. Arbritrarily declarations that exponential growth must stop soon are not meaningful in the positive or negative.

There are reasonable methods, however, to estimate likely outcomes of successful growth. I think its reasonable to predict that Bitcoin is likely to reach valuations of large publicly traded corporations. There are those that estimate it reaching valuations similar to gold, or the GDPs of industrialized nations.

But saying that the growth must stop because growth must stop isn't really saying much at all.