Without putting words in their mouth, my understanding is that they are not aiming to be top ranked on price. They are aiming to be the most transparent and convenient product.
With my legacy bank I get a free overdraft limit and a relatively cheap APR after that. However, I’m fully aware that their organisation steals from the poor to pay the rich by charging predatory fees to enable free overdrafts and huge switching bribes.
They also borrowed billions from the tax payer to avoid the end of civilisation, contributed to the sub-prime mortgage crisis, rigged the world’s LIBOR rate in their favour, promoted and supported money laundering for drug gangs in South America and more directly they have terrible technology, customer service and are generally an organisation that is rotten to the core.
If price is the overriding factor in your decision making process, then legacy banks or Starling Bank are definitely the places to be. Or you can just be multi-banked like most people these days, to get the best of all worlds.