Why are some apps are not available for Passport?

Right off the bat, I can see USA Today app is missing, I loved that app, now I have to get terrible NY Times app, it's not even free.
I also noticed several games listed as not compatible with passport.
If a device can run every android app by scaling the window, why can't it do the same for native BB apps?

Because it's not how Native Apps work, it's a matter of tough sh*t really, same with the 720x720 devices

You can usually use the android counterparts. It's usually because those apps are abandoned.