Make sure you don't only talk about social media when you talk about differences to 1920s.
There are many things that are either too ubiquous or hidden or too specialized in everyday use:
* useful encryption (unavailable before 1970s)
* LAN networks and popular internet (late 1990s), Tor (2002)
* directories, crawling based search (1998) and web 2.0 (coined in 2004, mainstream crash)
* web in our pocket (iPhone in 2006)
* crypto currencies (since 2009, intl. fallback where banking systems fail)
* web shops, online banking, ERMs, crowd funding ...
Now, in this world, power (Macht) means to know and care about hierarchical/centralized structures such as physical backbones (cables, antennas, fibers, satellites), search engines and their results, influencers and their funding, central certificate authorities, hardware production, crypto security...