Widespread electricity/internet outage would prevent any Bitcoin transactions from happening, reducing the value of Bitcoin overall.

EMP pulses could destroy individual ledgers. If those ledgers are not tracked anywhere else they would be completely lost.

Bitcoin is resilient to some things that fiat currency and commodities are vulnerable to, but it has its own vulnerabilities that those forms of wealth don't have. For instance, you can't actually really destroy gold, short of sending it off into space in a rocket.