Generally, whoever is perceived to be closest to the centre ground wins the elections in the U.K.
Whilst I agree that Starmer doesn’t need to shift anymore to the right, it won’t do him much harm in the next election as the Tories have become a party of no ideology. They’ve been taken over by neoliberals who have no morality.
No one can predict the future and you’re having a internal crisis as you have come to realise that the party you have always voted for you can’t vote for next time and are worried about what choosing another party might mean.
Ultimately, the Tories need to lose the next election and get all the class of 2019 MPs out and get people like Rory Stewart back in the party. The brain brain has been huge.