Yeah, it almost looks okay until you notice the "demo" banner on the top-right sliding in and out of view as the system struggles to update the window layout.
That means the app is running on VM with debug mode, it is slower than production mode which is native not on VM.
Why not run in release mode then to really show capabilities? Poor choice.
So if hello world is that slow, imagine launching anything non-trivial in debug mode to debug it :P
Debug mode has the same performance for 10 lines vs 25k lines, it's really just that it's running in the VM, and has debugging symbol. Performance is almost the same as compiled in my experience, although things like launch and resizing are slower due to how the VM works