One of the most attractive aspects of Chicago is its relative abundance of city parks. I grew up a few blocks from Warren park when it was a private golf course.
Senior housing is important but building this type of center in a public park is inappropriate. The land needs to be reserved for public recreational use. There are plenty of other spots that could be used for senior citizens housing.
If they can build a senior citizens center there, the next thing to do would be to sell the parks to developers in order to pay down city debts or some such. Don't sell off Chicago's patrimony.