In truth, that is precisely why our HDB estates undergo the Neighbourhood Renewal Programme and the Home Improvement Programme (often referred to as the toilet upgrading) not long after they reach around thirty years of age.
These initiatives are meant to gently refresh the estate and make it more comfortable for ageing residents — rather like turning the neighbourhood into a retirement village of sorts. There are more spaces and amenities for retirees to spend their time, along with thoughtful improvements inside the flats, particularly in the toilets, to make daily life safer and more accessible. It is all very much part of the broader plan.
So there is really little question as to whether Singapore ought to have retirement villages. In a way, the intention seems to be for each HDB estate to gradually become one in its own right, with the whole of Singapore functioning rather like a vast retirement village. After all, our public transport is already wonderfully convenient, and the RTS Link will soon begin operating as well.