This is in reference to using an army to break up a strike. In this case, the army would be doing the work that nurses usually do. That's not always the case, history would show you more violent strike breaking.
With internet and social media, you don't have to physically be outside of the place you're striking to deliver your message. You could have a group of people putting unmanned posters and stickers around with hashtags to the preferred social media site.
You can organize through messaging websites/apps; if the hashtag is taken down, the organized strike is still in communication and knows to not return to work. You can use messaging to make new tags for every one that's taken down.
During the beginning of pandemic shutdowns, it became obvious that just staying home for a couple weeks was enough to disrupt the economy. You don't have to stand outside in the cold/heat to strike. You can do it from the comfort of your own home. And still get the same message across.
With the increase of work from home jobs. Workers will have to find new ways to organize and strike when you don't work together at the same location.