I believe the new combination plug is compatible with J1772 connector, which can use the top part of the combination connection:
Nothing can use the bottom half by itself, as the control circuit and the proximity feed are in the top part of the connection. So a J1772 connector could use the top half, or a high amperage direct DC charging station could use the entire connector.
At one point, there was released tentative pictures of an J1772 which WOULD NOT have been compatible, but I don't think any of these were ever produced. Note the flat top to the outside ring of the connector.
I hope this helps clarify things.
Rich