Correct way to tag a stadium

On the wiki there is the example of London stadium:

Im wondering if the general tagging should be so that the building does not have the name but the leisure do.
Whats i wonder more about is that there is not leisure=track used in the stadium:

Is this the correct way?

The example with the London Stadium looks ok for me.

In a case of the London stadium for example, why there is no leisure=track around the pitch?

There doesn’t always have to be a specific reason. Maybe nobody has been interested in mapping it yet.