> academics I've talked with think the computers of the distant future will have no limitations.

This could mean a lot of liberal arts students. Academics aren't in any advantageous position to understand the progress of technology. Computers necessarily have limits because of their physical properties of matter and energy.

Thinking that "future = no limits = no scarcity = everyone gets everything they want even fantasy" is kind of a logical leap that most people in tech are not comfortable making. Maybe "academics" are more optimistic because they don't know anything, and it's easier to believe we'll have flying cars in the future than to realize that there will never be a time on Earth that it makes economical sense to fight gravity for an individual transport medium.