Hell even the California countryside is like this, once you get far enough away from the big cities
This is the key statement.
Build more SFH suburbs, gonna take you longer and longer to get far away from those cities.
Denser cities make it easier to leave them for a short stint, too, because there's less sprawl.
Yes, it's probably a good idea to live outside a city for a while in your life. Though that's up to individual preferences.
I'm not quite sure whether it makes much sense one way or another to say that the US is 'still not very dense'.
In some literal sense, that is obviously true. In another sense, just because eg Russia has huge empty lands in Siberia bringing down the average density on a federal level, doesn't really make a difference to someone living in the suburbs of Moscow.
Similarly, if Russia lost Siberia tomorrow, the person in the Moscow suburb wouldn't experience density any different either.
I only chose Russia as an extreme case example. You can replace Siberia with Alaska or the flyover states, and Moscow and its suburbs with eg San Francisco and Silicon Valley.
After spending years in quite a few different places around the globe, I'm quite happy to live in Singapore these days, one of the premier global cities.
In the US it is sad that because of building restrictions so many people are excluded from its most productive cities; unnecessarily setting back the economy and thus the prosperity of the people. Including even of those people who wouldn't want to live in those most productive places.
This will be my koan for the day.
Singapore has a size of 728.6 km2, and a population of 5.7 million people. For a density of 8,400 people per km2. (That includes water reservoirs, military bases, an international airport, areas for heavy industry, nature reserves, garbage dumps, power stations, 1.5% of the world's crude oil refining capacity, a few semiconductor fabs, etc.)
There are 7.96 billion people on the planet. That means if you scale up Singapore at the same density, you'd need 952,000 km2 to fit everyone.
Texas has a size of 696,000 km2. So our mega-Singapore would need about 1.37 Texases of area.
That's pretty close to your number.
Wikipedia gives New York City's population density as 11,313.68/km2, but the borders for that calculation will by necessity be drawn a bit arbitrarily. And I assume that doesn't include as much of the support infrastructure as Singapore does.
You're absolutely correct that there's heaps of wilderness in the USA, but the more SFH there is, the more sprawl that is required, which means that that wilderness is further and further away.
I'd rather get to the wilderness faster and not have to drive through hours and hours of sprawling SFH suburbs.
Then people shouldn't be allowed to ban their neighbours from building whatever housing they want.
What people really want is their work, stores, school of choice within walking/biking distance, which is harder to accomplish.
By the time I graduated college all of the empty fields and forests where I had roamed as a teenager were now developments.