I think it's certain that prices will go up. The Uber rep is obviously
concerned primarily about Uber drivers working in "the middle"
but there is also the issue of suburban PHV drivers who make only
one trip per day into central London.

If, for example, a driver takes an outer suburban customer to
Barts Hospital, that customer will be the only one that day
necessitating the driver to pay the surcharge. Presumably the
entire charge will be added to that passenger's fare. The customer
will not be pleased with Mr. Khan!