ATC services available, speed restrictions, visibility requirements, etc.
UK pilots tend to be mostly clueless about class E, the reason sure being that there is so little of it up in Blighty.
OK… let’s line up 100 German pilots and see how many of them know the ATC services, speed restrictions and min vis for VFR (day) and min vis for VFR (night) for each class of airspace!
Given that the vast majority of [insert your country, but Germany will do] pilots absolutely refuse to fly across any national border (ask any fly-in organiser, including a German one) I think the % would be an integer in the range of 0 to 5, with the value being inversely proportional to how long since he/she did any PPL or IR exams.
The whole drift in GA ops over the past decade has been
Stay cool. Not criticizing British pilots at all. Just a factual observation about them not understanding class E airspace very well because they never practically get in touch with it (as long as they don’t go abroad…)
All nations and their pilots have strengths and weaknesses. Even though a standard ICAO term, most German private pilots don’t know what an ATZ is; never even heard of it. Even the term AFIS is mostly unknown to them. Or the term CTA. Or what “booking out” means…
In the US there is a lot of Class E airspace but there are certainly a lot of airspace related acronyms used elsewhere that nobody would understand.
ATZ, CTA, CTR, TMA & RMZ come to mind along with ICAO… although oddly enough it is the fairly rigorous US application of ICAO ‘lettered’ airspace that I believe made those concepts (or similar) redundant. The US does have Mode C Veils around Class B airspace, which I guess is roughly equivalent to a TMZ.
I think the US also has one famously odd example of prior airspace classes – the Terminal Radar Service Area (TRSA) at Palm Springs, in California. I have no idea why they didn’t make it all Class C airspace when the FAA system transitioned to ICAO lettered airspace in I think 1991.
Regardless of country, I don’t see much need for airspace classifications other than A-F lettered airspace.