In Germany we don't say "Our autobahns don't have any speed limit" we say "Na toll, natürlich wieder eine Baustelle! Was? Bis 2036 wollen die hier ackern? Na schönen Dank auch. Jetzt auch noch 60?! Pff 70 ist mein bestes Angebot!" And I find it beautiful.
Some stretches do have limits. But even where there are no speed limits there are suggested maximum limits. If you're over that limit and have an accident (that normally might not be deemed your fault) you're more likely to be held liable.
That's not true.
About 70% have no limits, but if you're in an accident and you drove faster than 130km/h you can get partial blame.
On the other parts there are some kind of limits and they are as hard as they are in other countries. ( well, Germany does not have the biggest fines, but it's still a hard limit).