No, all strings theoretically exist in 𝛑 given enough digits, so longer strings don't reduce probability of existence, they just mean that it will take more digits to find them.
Are you saying that:
- given a long string, we might ask “can this string be found in PI?”
- the probability of finding a long string in PI is infinitely small
- the number of possible strings in PI is infinitely large
- it’s not possible to decide if the answer is yes or no?