While none of St. Louis's many disruptive interstates made the list, this example from Syracuse looked strikingly like downtown St. Louis's Memorial Drive/I-70 couplet.
Before

After

The transformation of I-70 and Memorial Drive downtown, and I would argue especially the elevated portion that divides Laclede's Landing from the rest of downtown, could be one of the greatest reclamation of urban spaces from deadening big-project planning that the city has ever witnessed.