If AI makes human labor dramatically less necessary, who buys everything?

Almost all discussion I see around AI and automation seems to focus on what happens to workers, but I’m more curious about what happens to demand tbh If AI lets companies produce dramatically more with dramatically less human labor, margins will obviously improve, but workers are also consumers. If a meaningful share of labor income disappears, what replaces that? Does the answer have to be UBI, broader ownership of productive assets, dramatically cheaper goods, something else entirely, etc? Curious how people here think this actually plays out if AI* Presuming it becomes as economically transformative as many expect