Salam `Aleykum,
First of all Allah has blessed you with the Sunnah of Rasul-Allah (saw), and he protected you from the deviance that those corrupt men fabricate and attribute to Ja`far and his father.
As far as conversions, there are some Muslims who were tricked into becoming Shia, especially in poor African countries or countries where there isn't any strong Islamic education such as Tunisia or Indonesia. I am from Sham and I do not know anyone who became a Shia but I'm pretty sure there must be some here and there. Another thing is, we've been observing that a lot of the Sunnies who become Shia (online), they usually don't stick to it, they leave it after a while and return to Sunnah or atheism or something else. On the other hand, quite a few Shia living in western countries are becoming Sunni Alhamdulillah, their numbers aren't big but they're quite well educated about Tashayyu`, that is because Shiasm is like brainwashing, it is hard to leave it for many reasons, this is why a lot Shia who learn about how corrupt their faith is still can't leave it and end up becoming something in the middle between Sunni and Shia since they're too scared to leave that religion. Additionally, as you yourself stated, Iran is putting a lot of money and effort into converting Sunnies to Shiasm, Ahlul-Sunnah are mostly oblivious and do not care about these issues nor do they know anything about the Shia faith so they can counter it.
That's kinda it bro.