As another anecdote, here in Austria, which for many things has similar laws to Germany, you can't have dual citizenship, and being born here doesn't confer citizenship on you, as it does in places like the US, or Italy. So our daughter will be Italian and American, despite being born in Austria (not that we would have wanted it otherwise, but still...).
I met a German guy in the states, who was born and raised there, considered himself German, but didn't get citizenship until 18 or 19 because his parents were from Turkey.
You can find a list of countries that deny citizenship to people born in that country of parents who are not of the "right" blood, yet have lived in the country for many years. It is one of the strongest indicators of institutional racism I can think of that is still in practice in many modern nations.
I agree with what you say, but that list seems mostly to be about countries that grant citizenship to people of a given "ethnicity"/stock that weren't born in the country itself (for instance, if you have an Italian grandparent, you can get Italian citizenship, even if your parents are, say, Brazilian). That's in contrast to countries that deny citizenship to those who are born in the country in question, which is what strikes me as too exclusive.
I met a German guy in the states, who was born and raised there, considered himself German, but didn't get citizenship until 18 or 19 because his parents were from Turkey.