it should be noted that until the 1990s the population of vienna has actually been slowly declining (from 2 million more than 100 years ago to 1.5-1.6 million) and most projects before then were more likely needed because a lot was damaged in the world wars. but in the last few decades vienna has seen unprecedented growth, now reaching almost 2 million inhabitants again. consequently in the last 20 years several new building projects have been initiated. the ones i linked are just a few examples. i keep finding out about more as i search.
but there is also https://en.wikipedia.org/wiki/Donau_City from the 90s (though it has only 20% residential use) and https://en.wikipedia.org/wiki/Alterlaa from the 70s
in general vienna has a long history of large public housing projects going back a century. https://en.wikipedia.org/wiki/Gemeindebau
it should be noted that until the 1990s the population of vienna has actually been slowly declining (from 2 million more than 100 years ago to 1.5-1.6 million) and most projects before then were more likely needed because a lot was damaged in the world wars. but in the last few decades vienna has seen unprecedented growth, now reaching almost 2 million inhabitants again. consequently in the last 20 years several new building projects have been initiated. the ones i linked are just a few examples. i keep finding out about more as i search.