This is a difficult question to answer, as one said: why is the Internet? Why the computer exists.
I think it's an easy question to answer.
Why the Internet? Because communication was too slow. People needed faster and more efficient ways to communicate and share information.
Why do computers exist? People needed faster and more efficient ways to be productive.
Why does Bitcoin exist? Because current monetary systems have fallbacks (inflation, corrupt, slow). And all the reasons shared in the video link in the OP. People needed faster and more efficient ways to send money without being stolen from by the government.
Each invention was created out of
necessity for improvement and solved a problem.
