Based on Tuscan dialect, but my understanding (correct me if I am wrong) is it was not 100% the same as that dialect and drew from historical written forms.

The fact that mutual intelligibility exists with other dialects certainly helps. But the same is attempted here to bridge Slavic languages.

But yes. My two examples are high prestige, emerging at the right time alongside a new national identity. It has better chances than some Slavic language bufs on the internet. Just trying to say that the line between "constructed" language and a real native tongue is sometimes blurry. Failure of these attempts is not inevitable, given the right circumstances.