Isopropanol is hardly the limiting reagent in this route, nor is it hard to produce by myriad ways.

Hell, even thionyl chloride (still tons of legit uses) is more of a red flag than IPrOH.

Something is definitely a bit goofy about this blog. Not saying attacks didn't happen, it's just that, from a chemical production point of view, iPrOH is a really odd choice to look at.