I modified the title for accuracy. The original title misleads, slightly, IMO: "When Will AI Exceed Human Performance? Evidence from AI Experts." I swapped AI out and replaced it with ML.

The paper itself uses the acronym HLMI (high level machine intelligence). Quoting:

"High-level machine intelligence (HLMI) is achieved when unaided machines can accomplish every task better and more cheaply than human workers."

So a collection of machines could accomplish HLMI, without needing any single machine to do it alone.