To be fair, the reason why many Japanese toy companies switched to die-cast metal was because it "was a great cost saving measure as companies put less money into expensive casting tooling" (ref). So basically it was done because metal was cheaper than plastic. Die-cast metal was phased out in 1986 as plastic had become cheaper than metal.
↑This.
Yup.
Having said that, I just bought the large Optimus Prime and Megatron for $60 each. As expensive as MP Dinobot and BW Megatron are, I'd wager that the size, complexity and engineering of those toys would justify their high prices (just as MP Sunstreaker's tech level justifies why he's x2 the price of MP Lambor). I reckon that I've been, in relative terms, been more ripped off than anyone who's purchased MP Dinobot.
Man I cannot wait to open these toys and be disappointed! (I've seen video reviews)#suckerforpunishment #buyersremorse