Not Iranians - what would anyone gain by influencing Iranians' views of Scottish nationalism? My experience has been that people outside the west barely know Scotland exists and are not going to care about it anymore than the average Scot is likely to have strong feelings about Laos.
It may be aimed at Scots but sometimes be done too blatantly so slips into the implausible. It may be aimed at influencing just those prone to conspiracy theories - who might be few but more likely to extreme actions.
People leave Iran for UK. The idea is that if UK seems less attractive and stable, fewer people will be strongly inclined to pursue it. It also normalizes chaos at home.
I think there are parallels to draw to how Fox News tried to paint a picture of places in Europe being on fire and overtaken by gangs and radicals years before that became close to actual reality.
As a Scot, I would assume it's an attack on the UK by supporting attempts to break up the UK. That seems credible. Who's behind it, is speculative.