>>>Web applications aren't like Melk Abbey, Queluz Palace, or the Grand Palais. They aren't meant to be beheld.
So is architecture, in a way. Living in a house is close to using it. It's almost interaction design. (Arguably, it's more true of houses than of monuments.)
It comes down to the level of intricacy in the usage. The extent to which I use...
...the Sistine Chapel - Stand in it.
...my house - Live in it.
...a web app - Click all sorts of buttons, encounter alerts, make micro-decisions.
As the intricacy of usage increases, so too does the risk of negative distraction (as opposed to positive distraction, like being awestruck by the Sistine Chapel's ceiling and not hearing a friend call my name).
My house: cook in it, sleep in it, exercise in it, practice music in it, work in it, build furniture in it, wash my clothes in it, entertain guests, dine in it and so on and so forth.
Most web apps: browse it.
Can't remember what my point is, but that you're oversimplifying on the first two examples and expanding the web app example.
So is architecture, in a way. Living in a house is close to using it. It's almost interaction design. (Arguably, it's more true of houses than of monuments.)