It would be interesting to see the answer to this follow up question to the people who prefer the slide out keyboard: "To get the slide out keyboard, you must have a thicker, heavier phone than the version that that doesn't have the slide out keyboard, and be limited in how you can orient your phone while typing. Would you still take the version that has the slide out keyboard?"
I suspect the phone companies have determined that enough people would answer no to that question to make slide out keyboards unprofitable.
It would be interesting to see the answer to this follow up question to the people who prefer the slide out keyboard: "To get the slide out keyboard, you must have a thicker, heavier phone than the version that that doesn't have the slide out keyboard, and be limited in how you can orient your phone while typing. Would you still take the version that has the slide out keyboard?" I suspect the phone companies have determined that enough people would answer no to that question to make slide out keyboards unprofitable.