it may change quickly in places with guaranteed electricity & network. Anywhere else tho, cash is superior because of reliability & brand recognition.
Discussion
the thing is that where there is stable power and networking is where it matters the most
these places you speak of as they are right now in the world mostly have adopted FRNs as their currency, even El Salvador was like this prior to Bukele
some places, like Venezuela, they tried to outlaw this and they ended up with so much cash they were using it as toilet paper
if power and networks are down, everyone is at the same level, and that level will be confined to local trade, because telecoms will be dead, and all federations and central authorities, not just like the us federal government or the EU, even the provincial/shire governments will be dead, the national payment networks will be dead
everyone will then depend on physical cash, but i think that's probably the least of the problems if the power and networks are down
starving entitled socialist brainwashed morons are gonna be the bigger problem, and all of a sudden nobody's gonna care about gun laws either
ignoring SHTF scenarios.. cash can get wet, and u don't have to charge your phone to use it. properties that make it superior everywhere except the (sub)urban jungles.
digital currency isn't superior for most use cases in impoverished places