That depends on your definition of "practical" and "entirety".
The article was about languages being used to implement Android. Clearly, no, you can't have an entirely memory safe language that can be used to implement Android, for the reason you said. But there's a wide gap between "practical for doing useful work of any kind" and "practical for implementing Android".
Then, "entirely". What's "entirely"? Entirely until you get to library calls? Entirely until you get to OS calls? Entirely including the OS? If you include the OS then again, you are right for the reason you said. But if you exclude the OS, I'm not so certain.
The article was about languages being used to implement Android. Clearly, no, you can't have an entirely memory safe language that can be used to implement Android, for the reason you said. But there's a wide gap between "practical for doing useful work of any kind" and "practical for implementing Android".
Then, "entirely". What's "entirely"? Entirely until you get to library calls? Entirely until you get to OS calls? Entirely including the OS? If you include the OS then again, you are right for the reason you said. But if you exclude the OS, I'm not so certain.