The are some major airlines on that list, and their bottom line will be really hurt by this. Several times a year I fly from Australian to Europe, and transit via the Middle East is a good option. Middle East transit is also a good option for New York (but not LA), and my wife is doing exactly that (Qatar) next month.
If I can't take a laptop to my final destination, I also can't take it from Australia to the Middle East. I'm not one of those constant workers on planes, but I do like to do a few hours, especially at the beginning of the flight. Not being able to use my laptop on a 24 hour flight is an absolute deal breaker. I will not transit in the Middle East - It'll be Singapore instead.
Business travel into New York or London will shrink dramatically for Emirates, Etihad and Qatar. Pity, they're all very good airlines. I wonder if commercial competition was a factor in this decision.