Durability and cost of materials are not the same thing just so you know,
Indeed I do know. Though I don't think what I said actually contradicted anything - the quality of plastics and fabrics is higher in both terms of feel and durability. I'm not sure how that correlates with "cheaper materials". In what way are the materials cheaper? In terms of volume? Sure. In terms of quality, or lack thereof? That's conjecture again.
reliability is something that has been improved over time though advancements in technology, its not as said before conclusive to costs of materials.
Technology directly influences quality, and technological advancement and improved quality come at a cost.
That can be materials as much as it is more stringent quality control procedures. I've been to a modern engine plant and seen the bins full of engine components that didn't pass quality inspections. That's despite engines being built to tighter tolerances than ever. I bet a British Leyland plant in the 70s didn't chuck out bits even if they had visible defects from poor materials and sloppy manufacturing processes. Yet the real cost of an Austin Maxi or similar is higher than most modern equivalents.
But you still need to clarify what you mean.
You said :
back in the 80s many mainstream cars could be sold with real leather, real wood and real steel and still be affordable
This doesn't make any sense. Cars featuring real leather were, in relative terms, as expensive back then as they are now. Or not, since even fairly basic cars now have leather wheels and gearknobs. Few cars use real wood, but that's mainly a stylistic thing. And this:
Also forget my Real steel claim what I meant was steel bodied.
...still makes very little sense. Most cars today still have a steel structure. Or steel and aluminium, which is more expensive. Or steel and high-strength variations of steel, which is also more expensive. Some cars have plastic wings or other panels, but I'm not sure I can see a scenario in which that's a bad thing, since they don't rust, absorb knocks better than steel, typically weigh a bit less and can be formed into all sorts of weird and wonderful shapes quite easily. Does using plastic fenders keep costs down? Potentially, though I'm not sure it's enough to make a point out of.
Platform sharing isn't new but it's much more extensive now then ever, complete driveline sharing is much more common then in the past too when it was fairly normal for each car to get bespoke engines.
Im sure your familiar with Henry fords production line and how the more and faster you build, the cheaper each part can be philosophy works.
Again, what are you actually trying to tell me here?
If you're trying to illustrate that a mid-engined sports car would be more expensive to build, then I need no convincing - I've already agreed with you on that.
But your original point was that the lack of wood/leather/steel seems to have some kind of bearing on why it's now more expensive to build a mid-engined car. Or something.
I think you're overstating the importance of platform sharing, too. It's not as simple as dropping different bodies onto identical chassis (like a Beetle - that other example of widespread platform sharing in the automotive industry). Take MQB for example - the elements that are basically identical throughout the cars that use it are very few. From memory, it's the front bulkhead and subframe, and elements of the floorpan.
Producing those as common parts does save money, as do common engines, but the entire rest of the car is pretty unique to each model. You can see that by comparing something like an Audi TT with a Skoda Octavia Estate. Despite what keyboard warriors will tell you, neither drives alike, the interiors are completely different, no exterior panels are shared, no suspension components are shared, and there's a crossover of maybe an engine and gearbox or two. And those are in different states of tune.[/quote][/QUOTE]
I reckon it'll be a MR 2-seater... the new MR2. Certainly hope so, my MR2 and my MX-5 were my two most favouritest-ever cars. The only thing that spoilt the MR2 was it being silver not black, but even so it handled very well 
