this makes me want to cry
This is true, they painted everywhere, and most of the example of outdoors rock art is found in other continents aside from Europe. Some examples:
The Zuojiang Huashan Rock Art Cultural Landscape, in Guangxi, southern China.
The Helan Kou Valley carvings, north of China.
Kakadu National Park, Australia.
Saimaluu Tash, Kyrgyzstan.
Horseshoe Canyon (Utah)
The quote is from “What the caves are trying to tell us” by Sam Kriss. It’s a gorgeously written article and I highly recommend reading it.