It's absolutely not redundant. At the end of the day, we would like to see an expert advisory panel, or an expert advisory body, that plays a part in advising all future governments. The ministerial panel is not part of the legislation. It is an advisory body that advises the minister.
As I said before, once the legislation passes through Parliament, these become Governor in Council appointments, and they are subject to the same kinds of things, which include requiring changes to the law to actually amend this.
At the end of the day, this is intended to be a forcing function on all future governments to ensure that they take climate action seriously.