Huh? If investors demand immediately profitability, wouldn't that push companies to "fail fast" even more? The point of failing fast is to spend as little time as possible working on the wrong ideas, i.e. to find 'market fit' as soon as possible.

Time spent designing and architecting isn't free either and, for a lot of people, 'implementing' is the only viable means of testing designs and architecture, and more importantly whether there are any (potential) customers.

An "exit through an acquisition" is a perfectly sensible goal if acquisitions are common or expected. It's pretty common in (some) other industries, e.g. pharmaceuticals.