Russia is currently in process of testing parallel internet which in times of severe conflict will turn into an intranet disconnecting itself from the rest of the internet.
If this happens, propaganda and disinformation would then fall back to era of traditional techniques such as Airborne leaflets.
5th Generation warfare is aimed at influencing perception of the people to sway their opinions about a certain thing through disinformation and propaganda.
Traditionally this was being done through airborne leaflets , loudspeakers etc However, due to vast adoption of social media it became easier to collect psycho-graphics and spread propaganda.
however since countries like China and Russia are building their own internet which in critical times can be completely segregated, in that case psychological warfare will revert back to traditional techniques.