"the inability to install desktop apps will protect users from many threats"
"the inability to install desktop apps will protect users from many threats"
We don't really think so, do we, though it might make for good PR fluff for a few seconds?
It will allow certain dim-witted types (PR-fluff merchants, IT helpdesk jockeys, IT directors) to convince themselves that many classes of threat are no longer threats.
But in reality, how many meaningful Windows threats ever needed to be installed like a desktop app, rather than just run as a simple executable (or, for the better exploits, opened and loaded like an ordinary document, with or without macros, or even just simple unauthenticated remote access buffer overflows ).
Those attack vectors are not in any way being blocked by being unable to install apps in general.
There is no meaningful security improvement here. There is potentially a significant cost increase (if you want this for business use) associated with loss of productivity, and a loss of convenience and flexibility for the home user. At work, those costs don't matter because they don't directly affect the IT Director. At home, you were only ever going to buy one anyway.
In any company with an IT Director, they'll likely be using Active Directory, and RT doesn't play in a domain/Active Directory environment does it? Or has that changed?
Let's see if it lasts as long as MS Handheld PC 2000 did. Much more interesting hardware for its time (see e.g. HP Jornada 720) but hampered by running a variant of Windows CE, and it didn't get much development effort anywhere, especially in MS.