In this scenario, the Cambrian and Heart of Wales lines simply aren't built, so that the only East-West routes to be built are the North and South Wales lines, along with the Barmouth-Ruabon line,. The only way to get to say Aberystwyth or Machynlleth from England is via Barmouth, Swansea or Bangor. All other lines built in OTL still get built, but these two lines are simply butterflied. What effect would it have on West Coast Wales?