What do you mean UKIP collapsed post brexit, the right wing of the party or the ERG is basically UKIP as the poster says they have been holding the party to ran

What do you mean UKIP collapsed post brexit, the right wing of the party or the ERG is basically UKIP as the poster says they have been holding the party to ransom for a while. Sunak needs to purge them from the party if he is to win another election.