All they are set up to do is being a local forum, co-ordinate local transport strategies (metros, local roads, commuter rail) with regional ones (intercity rail, strategic highways, rail freight, ports and airports) and fund transport studies.
They have no executive power over infrastructure, no capital budget. The only money they receive is operating costs and feasibility studies.
They have achieved what they were set up to do, create a regional plan, but now they haven't been given any resources to move towards implementation. Devolution stalled.