In any case, the result totally discredits Keir's strategy of moving Labour so far to the right that it's no longer distinguishable from the Tories- since, at 33.6% Keir's "changed" party won essentially no "Tory voters" at all.

And since the Right will be reunited by some means at the next general election- an early 1950s-style "electoral pact" if nothing else, Keir will now HAVE to reach out to the progressive voters he unnecessarily alienated, rather than continue to encourage his followers to keep demonizing them.

He never had any reason to treat the Left as the enemy, and he can only avoid being a one-term PM if he ends the war against the Left.

He can start by doing the simple, decent, obvious thing and instituting proportional representation for the 2029 election and for local elections throughout England(England is the only part of Britain that still uses the first-past-the post system for local elections) before that.