I've never seen convincing evidence that it has. Just the typical "oh but they have a phone and a TV" throw away comments, while ignoring that homelessness exploded during the 80's and is on the rise again over the past 15 years. That living anywhere that has jobs is impossible. That millions live in food deserts without access to healthy food. That education in poor areas is massively substandard, leading to generational poverty. That there are very real effects from living in high crime areas.
Middle class lifestyle has skyrocketed and so the expense required to maintain it is greater. What other evidence do you want? A average middle class family of 4 in the 60s often had a house with two or three bedrooms and one bathroom, one car, one tv with maybe 15 or 20 channels, one landline phone, no college degrees, and maybe one camping vacation or roadtrips to Grandma's house for major holidays. Eating out was a treat and if you wanted designer clothes, you designed them yourself...and you wore clothes until they wore out.
A middle class family today has a four bedroom house with three or four bathrooms, at least two cars, at least two tvs, at least four phones, usually all college educated to some degree, and at least one vacation to places far swankier than the KOA or Grandma's living room floor. Eating at home is now the treat, because fast food and takeout is the norm. All clothes are bought at the store and for a premium if you want the fashionable thing.
As far as food - In what part of the US can I not walk into a Walmart and find a bag of potatoes, a block of cheese, a bag of rice, a bag of beans, and a pound of ground beef or chicken? Add in some spinach or broccoli, and a carton or two of eggs, and for less than $50, you can feed yourself for two weeks with food that is much healthier than most middle class or rich families' diets. "Food deserts" are by and large a myth.
If I start on inner-city education, I will probably exceed the word count. At risk of omitting things, sum it up to say that, in spite of what is or isn't lacking from inner city schools, a lot of inner city people don't view education as important and the ones that do usually make something of themselves and end up breaking free from poverty.
Also, I don't mean to be crass or rude, but most homeless people aren't homeless because they just can't catch a break and are otherwise clean, hard-working people. There are some, sure, but most homeless people are extraordinarily mentally ill and/or have drug addictions and can't hold down a job or place to live because their addictions are more important than a place to live to them. That is an important issue, but only very, very tangentially related to wealth and income levels.