[MauranKilom]

We know for a fact that pi is truly infinite, there's no "if" there. But we are not sure whether it contains every sequence of (e.g.) decimal digits.

Either way, your proposition works for "the list (or concatenation) of all positive integers in ascending order" as well. There is no deep insight in it, even if it were also true for pi.

[tsukikage]

...pi isn't infinite, though. It is a finite number; not even a particularly large one - its value is between 3.1 and 3.2.