How is Obamacare good for the poor?

I'm not quite understanding why liberals think that this is such a good thing, except the liberals that own stock in insurance companies. One thing I know is that car insurance, which anyone who drives is required to have, is too expensive, especially if you're young because they automatically assume that young people are going to be reckless. Now, with the individual mandate, I expect that health insurance companies will jack prices up knowing that people have to have it, and they'll probably do the same thing the car insurance companies do; they'll charge more for young people because they're supposedly reckless, they'll charge more for people with preexisting conditions, they'll jack your premiums up if you ever go to the hospital, etc. How is this supposed to help the poor? Also consider the fact that there are a lot of people that will not take government aide, look at all the homeless people that are homeless because they refuse to go on welfare. How will taxing them for not having insurance help them?