The case for it being propaganda goes something like this: Barr's DoJ is making this charge publicly released so that the US can appear to be "tough on Russia." Despite Trump failing to condemn Navalny's Novichok poisoning or taking action regarding the intel on Russian blood-bounties on US soldiers. This would follow the pattern of other pro-Trump (painting him as a victim, or strong-man where convenient) politicized DoJ announcements such as 9 ballots being found in the trash, including noting that 7 of them were cast for Trump.
https://www.axios.com/trump-russia-bounties-taliban-putin-ca... https://www.axios.com/trump-alexei-navalny-poisoning-russia-... https://www.justice.gov/usao-mdpa/pr/revised-statement-us-at...