Look at crowdstrike. A tiny error disabled millions of computers for hours. Think about what would have happened, if this wouldn’t have been an error, but an actual attack.
Look at the supply chains of medical supplies. One major outbreak of some bacterial disease in India or China will lead to them stopping exports and since so many pills are produced there, a huge drop in global supply.
Look at the undersea cables. There are not that many and capable malicious actor could easily destroy a lot of them.
Look at the power grid. I don’t know about other parts of the world, but the European grid, spanning pretty much all countries in Europe plus turkey, has no plan for a cold start. If it breaks down, there’s gonna be blackouts for weeks.
Of course, none of that will end society, but that’s not how collapses work anyway. One event triggers another, and the combination leads to the collapse itself.