Stack Overflow needs to open source the code base for at the the Q and A portion of the product.  Then staff can switch from developing features to accepting pull requests from the community.

An "advisory board" will not have enough influence to get all the needed features onto the product roadmap.  Stack Overflow does not have enough staff to implement all the features that should be on the product roadmap.

Open source is the only way to get the development velocity needed to keep the site relevant and working well.