Quantum supremacy is 10-15 years out (from what I’ve heard). Is it normal for people to be worried about threats so far out? We don’t even know if Bitcoin will

Quantum supremacy is 10-15 years out (from what I’ve heard). Is it normal for people to be worried about threats so far out? We don’t even know if Bitcoin will exist then; only concern would be the cryptography that underpins it which is a greater issue.