I dislike the automatic assumption that greed or money is at the heart of this. The old saying 'Never attribute to malice that which is adequately explained by stupidity" seems to apply here.
I worked for a while in a law firm that worked in insurance, and handled plenty of home insurance claims, including a lot of house fires and apartment fires. The amount of engineering mistakes and oversights you'd come across in the loss adjuster's reports were astonishing. Often times the cheaper option would have been better... it was a lack of knowledge / experience / proper thought rather than greed. Sometimes it was down to a shoddy job, but almost always due to laziness in installation rather than cost cutting.
Worst case was the builder who worked his whole life to be able to afford to build his own home, finally built it, and three weeks later the whole thing burned down because he'd installed the wrong airflow system underneath the chimney. His three children very barely avoided death. Even when it's your own life, your own kids at stake mistakes can be made.
All I'm getting at here is that I highly doubt any of the people involved here thought "Yeah this cladding is a fucking flammable deathtrap, but fuck it let's pocket the five grand it would cost to use the better stuff and if people burn alive so what?" I just can't see a scenario where this was anything other than a terrible, terrible error of planning/oversight.
Now, if you want to start talking about the defeat of general fire safety legislation or deregulation or whatnot then I am 100% on board.