Minibanks charge a fee if they are not your bank, they have been doing that for a very long time. But you can get cash at many supermarkets.
The proportion of payments that are electronic has been very high for many years, cheques were effectively abolished thirty years ago and we have very rapid (seconds) and easy to use ways of transferring money between private individuals knowing only their mobile phone number (Vipps).
Nothing much has changed in the last couple of years except for the new law requiring the acceptance of cash and the issuing of a leaflet on resilience by the DSB to every household in the country which along with saying you should keep several days worth of water and food also says keep enough cash for several days use.
And this year has been declared a year of Total Defence.
See https://www.dsb.no/en/risk-vulnerability-and-preparedness/
