With the ISDN (https://en.wikipedia.org/wiki/Integrated_Services_Digital_Ne...) network, Germany had the most advanced digital switching infrastructure in the world. It offered two 64kbit/s lines into every household, and that in the 80s. Unfortunately, due to political decisions that were highly influenced by Leo Kirch and his commercial TV provider (Premiere), Germany's public telecoms infrastructure was a) privaticed into Deutsche Telekom and b) shifted to put copper TV cable into every household instead of fiber.
In east Germany, after reunification in the 1990s, Deutsche Telekom started to introduce a fiber into every home (OPAL - https://de.wikipedia.org/wiki/Optische_Anschlussleitung) but then they shifted their focus to DSL and reusing the old copper wires for telephone lines and abandoned this. No, not only abandoned. They opened up the streets again to lay new copper wire.
Upgraded too early to what? Letters and fax machines?