My thoughts on F1 stray fairly far from the pinnacle of technology view. Honestly, I just don't find it very compelling from a race fan's view.
I've been fascinated by hybrid technology but it hasn't improved the spectacle for others who do not share my geeky perspective. F1 technology is hardly mentioned in the promotion of road cars, and MGU-K and MGU-H are amongst the least informative acronyms invented. Was there anybody at the FIA or manufacturers pointing out that new technology needs an exciting name? If manufacturers aren't using it to sell cars, something is wrong, and the manufacturers are wrong in pushing the FIA to retain the current engine model.
If we look at the previous F1 rules package -- naturally aspirated engines plus KERS -- it reflected real world developments. It was also relatively open in that two companies could lead development of the engine bundle. Theoretically it was possible to mix and match ICE and KERS elements. The current rules have led to engines which are a long way from real world application. They are highly integrated -- no chance of mix and match -- and, against the odds, engineering teams have put together laboratory concepts in ways that work for thousands of miles. There will be cross over technology that ends up in affordable road cars but we are years away from exhaust pipe energy being used to directly drive wheels. (IIRC, exhaust pipe to wheel energy concepts have been around for a century but are still too impractical for defence applications where buyers have the biggest budgets for ICE-based engines.)
F1 has developed some fascinating technology in recent years, but the FIA should consider whether it matters. I initially thought that the current rules might allow an ICE developer to team up with experts in turbines and electrical power to develop an independent package. The solutions created by Ferrari and Mercedes-Benz quickly erased that idea.
The big car manufacturers involved in F1 want rules which exclude outside competition. The current rules demand that an engine builder is big enough to do everything as the major partner -- suppliers are entirely junior. The volume manufacturers plus Ferrari, wealthy enough to develop an integrated engine package, might welcome an intervention from Ford or Toyota because it means those companies are not spending £500 million on production car design or something equally beneficial. Volume car manufacturers do not want to be beaten by an upstart company assembling a package using almost-off-the-shelf elements.
Given cultural and environmental concerns, where ICE-based vehicles with KERS will be a minority amongst electric vehicles, I think the MGU-K/MGU-H concept has run its course. It will never be practical in the real world. If volume car manufacturers want 'relevance' as part of F1 engine rules, they'd be demanding ICE/KERS combos with the ICE reducing in size over time, or racing pure electrics versus hybrids. If the FIA appreciated that it is unwise to rely on volume manufacturers for the entertainment, they'd back rules which reduce the cost of competition.
I believe that Formula E has a long term contract to be the only FIA-approved electric powered single seater series. Maybe F1 will have to stick with ICE-based power. Would a 50cc two stroke be enough?
Apologies for use of acronyms and tautology (ICE-based engines).