They're fragile as heck, though, and contain mercury (albeit a small quantity in a relatively less-harmful form). Breakage needs to be handled appropriately, and disposal is as hazardous waste.
LEDs are more efficient, offer better (and often more flexible) light quality, are damndably rugged, and have far less toxic material load. Given the balance, I'd be swapping out CFLs (and have been).
Something sad about that, really.
That doesn't mean they always actually invested the money to rebuild properly... but it was sound engineering theory.
Of course, there were other financial shenanigans too- see https://en.wikipedia.org/wiki/Cr%C3%A9dit_Mobilier_scandal
Just today there was a newsletter from Construction Physics about Strap Rail. Literally wooden rails with a iron plate strapped on top put in the mud. Only in the US, 10 times cheaper. But more expensive to maintain and gone in years instead of decades for normal iron rails though.
But since then there was an endless stream of negative press especially in English speaking countries against German energy policies, so not much of this positive comments are still remembered.