The point is that it's hard to pick the fraction size. US national debt vs Italian lira/Swiss franc exhange rate, humans generate numbers of wide ranging scale

The point is that it's hard to pick the fraction size. US national debt vs Italian lira/Swiss franc exhange rate, humans generate numbers of wide ranging scales and yet it's convenient for computers to deal in fixed size datatypes. Hence floating scale. But yeah, it's a compromise. I expect these new types to catch on and be added to various language standards over the coming years, but we'll see.