Hi,
I disagree with this being "chicken or egg" issue. The people buy what it's advertised.
Prove: Nobody bought a smartphone before after apple invented one, and that wasn't an impediment for design a smartphone or selling it afterwards.
I have 2 qwerty phones; the HTC TyTNII and the Xperia mini pro 2. Now I have a Samsung S3 from six months and writing on a screen is the worst thing I ever did on a phone. I often come with an irresistible temptation to smash it against the wall. I've tried several keyboards and autocorrector configurations (and no autocorrector) and it's the same. With the qwerty keyboard I was able to write without even looking at the phone; now I have to look, write slower and even looking and slower I make many mistakes. It's so bad that I get here finding info on phones to replace the s3 and I'm think I'm buying a photon q or an enact to replace my s2 thought they're older phones.
I believe the end of qwerty is due to profit. The people will buy what's advertised and on price. And the manufacturers rather to sell the phones with more profit margin. Any qwerty keyboard will add cost to the end user or reduce the profit margin to the manufacturer. And both things will reduce profit.
I see no impediment for making and 4' HD screen with a qwerty sliding keyboard below. Or this things couldn't exist:
Add a QWERTY keyboard to your Galaxy S3 | Mobile Fun Blog
Regards,