Apple writes their own device drivers and they write them to the extend their software and hardware needs it and no step further.
All this because osx doesn't do a thing that apple never claimed osx did.
http://en.wikipedia.org/wiki/Usage_share_of_operating_system...
I fail to see where your frustration is coming from, or why it's targeted at Apple. It's most likely just a calculated cost savings measure.
I'm not sure where you think said frustration should be directed.
Mini DisplayPort Connector
The Mini DisplayPort Connector is a small form factor connector designed to fully support the VESA DisplayPort protocol. It is particularly useful on systems where space is at a premium, such as portable computers or to support multiple connectors on reduced height add-in cards.
https://developer.apple.com/softwarelicensing/agreements/min...
2) Apple doesn't prevent you using dual monitors via other means e.g. USB / HDMI.
3) Microsoft/IBM had ridiculously high market shares (>90%). OSX is around 10%.
Someone would need to write the driver for this functionality. I expect Intel is happy letting apple do the work, but so long as that is the case, Apple has no need to support every hardware and protocol under the sun. They merely have to support their stuff fully, and beyond that it is someone else's problem.
Intel wrote the driver for windows, and it works on Windows. That's also apples and oranges IMO.