No, not forever. But for now, yeah. If a year from now there is a vaccine and/or a universally effective treatment that would render the virus to "just the flu" status, then games could go on as they always have. But until then, when the virus is highly contagious, potentially deadly, and wildly inconsistent in its effect, there can be no treating a single positive test as an isolated instance. A few days ago, this thread was filled with folks excoriating the stupidity of the Marlins playing a game on Sunday despite three positive tests, and now when the Cardinals do exactly what we all said the Marlins should have done, that's wrong?
The priority should be safety and well being of the players, coaches, umpires and other personnel in MLB. Having potentially infectious players on the field coming in contact with others is the opposite of that priority.