Here's how I'd break down the two types of users: People who are using AI to teach themselves how to work in the domain they are interested in, and people who are relying on AI to do all or most of the heavy lifting.
I'd argue that the people using AI most effectively are in the mostly-chatters group that the author defines, and specifically they are using the AI to understand the domain on a deeper level. The "power users" are heading for a dead end, they will arrive as soon as AI is capable of figuring out what is actually valuable to people in the given domain, not generally a difficult problem to solve. These power users will eventually be outclassed by AIs that can self-navigate. But I would argue that a human that has a rich understanding of the domain will still beat self-navigating AI for a long time to come.
I'd argue that the people using AI most effectively are in the mostly-chatters group that the author defines, and specifically they are using the AI to understand the domain on a deeper level. The "power users" are heading for a dead end, they will arrive as soon as AI is capable of figuring out what is actually valuable to people in the given domain, not generally a difficult problem to solve. These power users will eventually be outclassed by AIs that can self-navigate. But I would argue that a human that has a rich understanding of the domain will still beat self-navigating AI for a long time to come.