I think the "IFR on a vanilla PPL" is a complete red herring... the UK is also the only place I know of where you can't fly VFR at night, so allowing a vanilla PPL to fly IFR is necessary to allow night-flying!
Comparing airspace classifications across countries is dangerous. The ICAO may believe that Class E is the same across the world, but in practice we know that's not true. I wouldn't fly through Class E airspace in the UK without talking to a controller if possible. People fly through class E without talking to anyone all the time in the US. That's because Class E means something different. I don't think a Class E airway in the UK would work. Class F, maybe - we have them already, but not very many of them - but not class E.
Another example - way back at the start of this thread, someone (slim_slag?) mentioned that Gatwick was "only" Class D. Yes, Gatwick is Class D, but Class D is the highest level of control any airport in the UK has except Heathrow (and Northolt, but that's only because Northolt is in Heathrow's zone). In the US, Class D is used for the smallest of controlled fields, the equivalent of, say Cranfield (which is actually Class G). So, no matter what ICAO would like us to think, comparing airspace classifications across countries is not valid.
If you want to compare different countries, you have to compare what pilots can do in practical terms. American pilots can fly in IMC just about anywhere they want. UK pilots can't without jumping through a ridiculous number of hoops first. That's what it boils down to.
FFF
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