As the article clearly states, privacy features have been in the census since 1990. It is just that the previously used privacy feature was not very strong and could be defeated. So it was replaced by a stronger feature in 1920. Before 1990 the census. 1990 was when personal computers were being popularized and the computing power available to individuals exploded and so then it was possible to use computers to separate out individual information from the data the census publishes. So the issue came up then.
No it is not an overblown problem.