You can't have solarpunk without urbanism. Any "environmentalists" that pretend otherwise are lying. Neither skyscrapers nor mass single family housing are sustainable.
There's a reason the past 2000 years of urban development have been in rowhouses and smaller multi-story buildings.
The most powerful environmentalists are anti-urbanism. Every major environmental movement supports only single family homes. Environmentalism has as much to do with helping the environment as the Democratic People's Republic of Korea is a democratic republic of the people.
There's a reason the past 2000 years of urban development have been in rowhouses and smaller multi-story buildings.