Hogwash? More like state-backed propaganda disseminated by so-called objective and professional media organizations in order to justify an offensive war against Iran; a war that has achieved virtually none of its stated aims.
I personally trust OSINT sources more than NGOs these days. I would wager that the security forces numbers are higher. I would also wager that the majority of the deaths were CIA and Mossad backed insurgents operating in the context of a wider, legitimate, civilian-led protest movement.