You can definitely afford it, you just have to not live like a typical modern American.
You can arrange your life around riding the bike and taking public transport, get a roommate, cook your own meals, etc. etc. and live on $20k/yr or less. Not in an expensive metropolis (easily), but there are plenty of other places where you can live.
Look at how big houses were in the early 1900s. And how often people ate meat.
Maybe if you are single, young American without any health issues or dependents, sure, why not. Is it attainable by everyone? I don't think so. It's a great ideal to have, and maybe someday a reality, but as things currently are, unrealistic.
You can arrange your life around riding the bike and taking public transport, get a roommate, cook your own meals, etc. etc. and live on $20k/yr or less. Not in an expensive metropolis (easily), but there are plenty of other places where you can live.
Look at how big houses were in the early 1900s. And how often people ate meat.