BRK contains airlines but also primarily mining. The business model is to grind mountains until they are transformed into dust, then into toxic mud.
Transforming entire mountains into dust takes phenomenal amounts of oil, which makes mining by far the most polluting industry of our time, and BRK the largest shareholder of the most polluting industries of our times.
Return on investment in BRK is directly derived from burning the planet, and will be directly responsible of the scale of the migration events that will happen when hundreds of millions will starve.