The problem was that the right-wing of Labour sabotaged Foot(some departed and formed the totally unneeded "Social Democratic Party", knowing when they did that all they could ever do was guarantee a Tory landslide...an SDP-Liberal government was never going to happen, no matter what, some stayed in side and all they could internally to undermine him).
The message of the Eighties is not that Labour must always treat socialists as the enemy.
It's that the party needs to use media(including social media)well, needs to communicate its message coherently and concisely, and needs unity.
Labour has nothing to gain by putting the cynical, dismissive "professional politicians" back in charge...the people whose message to the electorate is "we hate activists and principles and we accept the idea that politics is about nothing at all but gaining power"-and who assume that the only way to gain power is to be as close to the Tories on the issues as possible.
Most of the people who are involved in this coup were demanding, before Corbyn won the leadership, that Labour support the Tory benefits cap and the Tory budget charter. Most of them were unalterably opposed to any reintroduction of internal democracy(they LIKED the fact that ordinary paid-up Labour members had no say in what the party's policies were and that the party conference was a bland, powerless, passion-free zone). What could possibly be improved by putting the people who lost the last two elections back in charge and telling the tens of thousands of good, idealistic people Corbyn has drawn to the party that they aren't welcome and should either shut up or go away? There is no huge block of voters waiting for the party to do that.