The Decadal Survey on Astronomy and Astrophysics 2020 (Astro2020), assembled by a 20-member steering committee and 13 expert panels gathering input from across the community, highlighted the crucial importance of theoretical models to support large observational programs in the Cosmic Ecosystems science priority. The final report featured an image from our cosmological hyper-refinement simulations to illustrate the multi-scale nature of gas flows from the cosmic web down to supermassive black holes!