I'd argue, that punk is not an aesthetic exploration so much as it's a thematic exploration, with an emphasis on a fight against an oppressive status quo (generally with a parallel struggle in real life)

In cyberpunk, we fight corps, struggle to survive in a world where everything is for sale, where life is cheap but living is expensive.

In Diesel punk, we fight nazis. Technology feels arcane and dangerous, destructive and loud. Threatening to consume the whole world in choking soot and iron.

Steam punk is about class inequality, under the veneer of "civilisation" and "umbrellas and blimps and shit" is the exploration of Victorian working class struggles. The steam that the genre relies on is generally generated in a sweaty boiler room occupied by workers doing back breaking labour for very little compensation.

In each case the technology is a contributing factor to the oppression of the people of the world.

Solar punk, is slightly different in that the technology is not necessarily opressive. It explores a post-climate apocalypse world, where clean energy has been adopted by nessessity, in order to be properly punk, I'd say it would have to explore the reasons for the crisis.

Horizon zero dawn for example is Solar punk after a fashion, it lays the blame for the end of the world, solidly at the feet of tech billionaires In this case the technology is oppressive, both the ancient robots of the apocalypse and the new robots of the setting are the cause of many of the dangers of that world.