Fiat currency has no intrinisic value in much the same away as cryptocurrencies.
There is a need for Bitcoin to exist and it is thriving.
We are not anywhere near the time when blockchain technology is obsolete.
You mention an internet shutdown rendering cryptocurrency valueless. The internet is now a fundamental part of human civilization. The internet will only shut down when the end of civilization occurs: in such an event traditional fiat currency will also be valueless.
Maybe you feel you missed the crypto-boat or you lost some money or something. It's not too late.