Someone can probably build an app player for android apps, but architecture wise, what you just described sounds kind of like a custom UI for android.
The rationale for not doing something like this philosophically is that the underlying point of webos is that it shouldn't feel like a 'whole new platform' to a web developer, but rather the platform they are already most familiar with, even more than android, i.e the web.
The rationale for not doing something like this philosophically is that the underlying point of webos is that it shouldn't feel like a 'whole new platform' to a web developer, but rather the platform they are already most familiar with, even more than android, i.e the web.