Smaller displacement turbos ...
Turbo 4 bangers. What is this, Indy cars from the 70's?
Costs and other things are always a factor.
One of the reasons the major American manufacturers limit their enrollment in Formula 1 (along with Le Mans Prototypes) is cost. It really does not net much marketing here in the US, and it's a drain that is unnecessary. American companies are about margins and volume. That's why IndyCar exists, as well as things like IMSA GT and GrandAm (although GM is involved with Le Mans, ACO sanctioned, FIA GT class today, Dodge was prior). This is much like other considerations in the US, like the Super Sonic Transport and Super Jumbo. American manufacturers did neither, but instead focused on fuel economy and distance.
So it can also have quite a bit to do with "technology transfer" from racing to production as well, beyond just cost. In a tightening world economy, at least for the west, there are these considerations for Europe as well.
The smaller 4 cylinder engines will put out the same amount of power as the current 3 litre engines with a new modern turbo 1.6 litre that will also need to use 60% of the fuel currently used.
Yep, there is still the engineering challenges of an I4 with turbos at a small displacement. It can lead to major advances in actual, production solutions. The world is moving to sub-2L turbo-charged vehicles more and more for economy and performance.
The new Gen-Y American consumer has very much embraced such, and Ford is the first company to actually make loaded, high-end compacts and economy vehicles. Fiat is looking to do so with Chrysler's new line as well. GM has compacts and economies, but does not put higher end options in them in the US for fearing competition with their V6/V8 products, even if their non-US subsidaries do (although lines like the German-designed Cruze is ready-to-offer them if and when Ford/Fiat sales so Americans are open to such). Even VW in the US has started to come up with inexpensive, option-bare vehicles for just the US market, because Americans have often been allergic to spending much on an economy/compact.
But back to racing and technology transfer ... the US' IMSA GT series in the '80s can be credited with maturing a lot of commodity solutions today that are cheap thanx to economies of scale like ABS, Traction Control and other things. There's also something to be said about the expanding area of electrohydraulics that started in American racing, then manufacturing (Corvette F55 option), and are now spreading to world class sports cars (Ferrari 599, Audi R8, now others). Eventually this technology will make it to all sorts of components, incluing valves for complete, fully variable valve timing.
Understand I say all this as an American who is
not a big fan IndyCar, and prefer Formula 1 (much less can't stand NASCAR). But even Formula 1 seems a bit "off-the-reservation," hence why I prefer sports car racing, which leads to real changes, let alone things I can drive if I so desire (even if I borrow a friend's or rent one instead of buying, to save money as I don't need such).
Formula 1 is filled with world class drivers, a lot of money and manufacturing and a lot of pressure. But I still love Grand Touring type of Sports Car racing with a more relaxed atmosphere, endurance racing and sportsmanship. There are still manufacturers and still great drivers, but the focus is on seeing what's coming next for production in many cases, or showcasing the best ideas. And it's still affordable for privateer teams, who surprise everyone at times.
I don't think Formula 1 will ever be IndyCar. Some Americans still want their own rules, and while I think that is wrong (hence why I side with Panoz and the ALMS side that the US should join the ACO/FIA instead of being separate), there will always be some reasons. But if Formula 1 can one-up American series in what transfers to real-world production, that will only garner more interest. One way to do that is with a sub-2L turbo, showing off European engineering and its superior experience at such.