You're technically correct, but try explaining all of this to a lay person or politician with no interest in mathematics or computer science. "Solving complex math problems" is a good enough explanation for them.

Majjin

bitcoin

Btc Bill Text - Texas

Gian

This is not "complex math problem solving". It's just trial and error by putting a value in a pretty simple hash function algo which can be executed by hand. An extreme case of a complex math problem is Fermat's Last Theorem which took Andrew Wile's decades to solve or supercomputers solving difficult calculation problems.