Moving into micro houses isn’t going to cut it, you’d need to slash US economic activity to reduce those numbers (an entire new technology).
We're not going to solve climate change by democracies adopting high carbon taxes.
There is simply no way developed nations are going to curb their emissions enough in time, and that developing nations will refrain from increasing their emissions, for us to avoid this disaster.
We might as well get used to the idea that our civilization is going to collapse before too long, and there's really nothing we can do about it. Other civilizations in the past collapsed and disappeared because of environmental change, and ours will be no different.
Our globe-spanning communications seems like it should help us solve these problems together, but instead look what it's brought us: anti-vaxers convincing a lot of people not to vaccinate, which has now brought back diseases we thought were almost extinct. Instead of using these communications to convince people about real problems and solve them, these communications have instead enabled the stupidest people to have a much larger voice and influence, which has led us to disaster politically in the US for one (just look at who we elected in 2016).
Sorry, but I don't see how there's any way out of this mess. We can't just figure things out in 50 years and then start fixing the problem; by then it'll be far too late.
The massive living spaces we have now are not sustainable. By 2050 if we are to avoid 2 degrees of warming we need to be emitting 2 tons of carbon per year per person: http://insight.gbig.org/targeting-2-tons-closer-than-we-thin.... The average American today emits 11 tons, whereas 2 tons per person is closer to that of someone living in Brazil or Egypt.
In climates where you need to heat and cool a home, carbon taxes will make heating and cooling the living spaces we have now financially impossible. People will drive demand for these smaller living options out of necessity. Additionally, as we make consumption less and less economically attractive people will have fewer things to want to store anyway, and personal vehicles will likely no longer be something the average person will be able to afford or want so there will be less need for parking and garages.