Toyota is more than happy to sell EVs to the UK. This is about not wanting to stop the production of other types of vehicles for Toyota's other markets, which they also want to serve.

Toyota revenue by region (2022) in trillions of Japanese Yen:

    Japan: 16
    North America: 11
    Asia: 6.5
    Europe: 3.9
    Other: 3.0

As with everything else, as the world fragments into different blocs, there will be different requirements for each bloc, and Toyota wants to remain a global car manufacturer.