I'm skeptical about this claim that multimonitor setups are common, but I have no data. Do you? I have only ever seen multimonitor setups common in a few verticals like trading, but that's not data, that's anecdote.In many office jobs, people connect cheap laptops to multiple cheap monitors. They don't need fancy computers, and even the MBA is high-end from their perspective. They just need to have several documents visible at once.
I dunno how expensive in die area it would be to support a third display, but apparently it's been too expensive so far. I'd love to see Apple support a third screen with the base M3, but I'm not holding my breath.Tight integration means making compromises, and the same compromise never works for everyone. Multi-monitor support is a low-end requirement, but it's particularly expensive for Apple, due to their insistence on very high resolutions and minimizing power consumption.