Not really, it is typical Labour reactions to gaining power, even when they expected it.
In fairness Blair and Brown came close to 'being prepared' after the years under Maggie Thatcher, and when John Major tried to hold the Tories together.
Perhaps only Harold Wilson was 'ready'.... if not exactly 'prepared', because he knew his 'majority' was slim very slim!
Labour's 'wide church' membership; predominately 'left-leaning' in terms of its troops, but some 'old fashioned right' members as well in the PLP, always tend to 'kick one another on the shins, under the table, whilst in opposition, but soon as they got into power internecine warfare erupts.
McSweeney, seems to have persuaded Starmer to try 'the iron fist... in the iron glove' to compel obedience from MP's, but as he now admits they simply didn't know how much the world had changed.