There have been plenty. Surely you aren't arguing that social media has never done so. Arguably social media has been one of the most catalyzing political forces in human history. And bearing in mind that "political action" can be in any direction, I found some examples. I didn't work very hard because this could have literally been a Google search on your part.
famously the Arab spring
also BLM, israel palestine
and the genocide in myanmar, that was definitely accelerated political action
There have been plenty. Surely you aren't arguing that social media has never done so. Arguably social media has been one of the most catalyzing political forces in human history. And bearing in mind that "political action" can be in any direction, I found some examples. I didn't work very hard because this could have literally been a Google search on your part.
Arab Spring
Nepalese Discord Protests
Euromaidan revolution in Ukraine
2009 Iranian presidential election protests
2011 Egyptian revolution
#BlackLivesMatter
#MeToo
Hong Kong protests
#NoKings protests
Yellow Vest protests (France)
Anti-Israel/Pro-Palestine protests
Anti-vaccine protests during COVID
Rohingya genocide
GamerGate
The case of Iran in 2009 is notoriously false. See for example what ForeignPolicy has to say about it.
More in general, Malcolm Gladwell is not convinced about the power of social media...
https://archive.is/GryvI#selection-323.0-355.16