@greenteafiend you sound very over-invested and angry about this. Why are you so angry that people think of the place they have lived in for 35-40 years - and raised their children in, as their 'home...' ? 
Why are you so keen for people to give up the home and garden, (that they have paid 10s of 1000s of £££ in rent for over the 35+ years they've been there (along with 1000s of £££ making it nice,) for a shitty little flat - probably in a dodgy area - with no garden, no privacy, yobbos hanging around in the stairwells, and people living above, below, and both sides?
Also, what gives you the right to assume most people in their 50s and 60s are in perfect health and can walk up multiple flights of stairs? Whilst some people in that age group are in good health, I know many who are starting to struggle health wise, especially with their mobility. How dare you assume everyone under the age of 70 should be shoved in an upstairs flat?!
You sound so bitter and angry, and like you're projecting. Like hell would I move out of MY 3 bed house after 35-40 years of being here (with its 2 extra bedrooms and a lovely garden) purely to suit the likes of YOU. It's not my fault the councils have sold off much of the housing stock via the right to buy, and not been fucked to build an equal amount of new homes to compensate.
I also find the thought of people who OWN a house with 'spare bedrooms' having to give it up for a bigger family ludicrous too!
Me and DH own our own house outright, and have no mortgage, and it has 3 bedrooms. If it were up to people like you, we would have to sell it and buy a 1 bedroom flat! LOL, fuck that! We will stay in our lovely 3 bedroom cottage in the countryside, near the woodlands, with its quarter acre of land, ta very much!
Blowing out someone else's candle, won't make yours shine any brighter you know. 