However the make-up of the City of Wakefield might be, the fact remains that all those towns are part of an official city. It is not for us to determine what makes a city a city. If they have been granted city status then they are a city. Even Plymouth became a city by "throwing a blanket" over the three towns.It's not that people don't like it, it's because a blanket has been thrown over many totally separate towns (Castlefield, Featherstone, Pontefract, Ossett... the list goes on and on and on) in West Yorkshire and given that metro area the name of City of Wakefield.
No reasonable person thinks Wakefield itself (population 99k) is bigger than Plymouth.