This seems more significant than their just announced price cut on dongles. Apples to oranges really, as they easily knew how every purchaser of a 2016 MBP would be forced into multiple dongles—IF apparently not the degree of uproar over it. But these external screens not only represent a sizable purchase but also a more selective one, as most customers will not need to rush into a purchase.
One might surmise that neither the design nor price of these external monitors met with the expected approval, thus now some attempt to salve the latter.
For myself, not impressed. The internals might be fine, but not only are these not Apple monitors—as one might expect—but in appearance nothing special. Something one might be willing to pay a premium for and take some pride in, just enjoy looking at.
Too, Mr. Cook's logistics lately seem questionable at best. If not always, Apple generally had their act together and product ready to sell on the day of unveiling, or shortly thereafter. Now, it seems more likely the question is how long the wait (in months) until delivery. Perhaps he is being judicious in not putting too much of Apple's resources into product they may not be able to sell. But as one could make some educated guesses on likely initial demand, and then ready to quickly meet that additional, anything less seems specious. As in either they do not care and/or are simply incapable of such basic manufacturing logistics.
Then as far as what one would be waiting for in a new MBP, that is another conundrum.