If people paying $5k would prefer to pay $3k for their units, why would this logic not also apply to people who are currently paying $3k?
If lower rents would make the city become undesirable, why did people want to move there in the year 2000, when rents were much lower?
The inherent property of a 5k rental he's referring to is that it costs 5k. Most people paying 5k for a studio just _don't want people around their houses_ specially if they are poorer than them. Otherwise they would be paying less than 3k for a room with a shared kitchen and bathroom or renting a bigger place with roommates.
The entire basis of capitalism in the US is that the work of the poor is exploited by those with the capital to build factories and businesses which extract labor and resources from the poor people
That's why they can't invest. You have it entirely backwards
Having said that, what's even worse than me is "low income" consumers. A lot of affordable housing, especially HDFC apartments, end up in the hands of the children of the rich. Not only are they not producing anything of value, they're also costing us tax dollars.
A gross oversimplification, but if you somehow make ten thousand new apartments available in Manhattan at $1k/month, they will eventually fill up with low-income tenants, which will make them undesirable. Pressure on all the existing $5K properties will remain the same.