The problem with tooltips is discoverability. The idea of this change is to make the wiki descriptions plainly obvious to even brand new users who wouldn't know

The problem with tooltips is discoverability. The idea of this change is to make the wiki descriptions plainly obvious to even brand new users who wouldn't know such a thing exists. My suggestion would be to only show one of these descriptions at a time as a sub-element of the first suggestion displayed in the old-style list (with other suggestions displayed as well, but without the description). This would make the description plainly obvious to a new user, but without the information overload presented in the current tag suggestions.