I’m not sure why they would reduce party influence either. Features like being robust against spoilers would seem to most benefit major party candidates.
There only functional difference between it and say, the original French two-round system that Maurice Duverger (of Duverger's law) contrasted with FPTP is that someone who wins an outright majority in the first election (an open "primary" in California) is not immediately elected.
The fact the second round is FPTP doesn't change the overall voting system. With only two candidates for a single seat, most voting systems degenerate to FPTP, but none of the issues related to FPTP are present either (there are no clones, no strategic voting, etc.)
For majors the benefit is clear: you don't get spoiled.
For minors, you don't have to overcome the barrier of being a spoiler if the race looks remotely close.
And of course voters are not disadvantaged just for having two acceptable choices rather than one.
Labour also picked Jeremy Corbyn an election back. Ultimately the rest of the country didn't want to vote for him.
The libdems of 2024 have a very different situation in that despite the Tory implosion they are weaker than ever. I'd put my money on them either still making the deal or getting buried if Labour had even more votes.
Labour now hasn't united its opposition because I think nobody fears it much.
Labour's opposition not being united is probably more attribuable to the Conservative party itself not being united. The amount of voters leaving the Tories to go to the Lib Dems and Reform has steadily been increasing.
Besides, a significant part of motivating people to vote against Corbyn came from Starmer's wing of the party itself.
Labour's electoral prospects improved because of the implosion of the Tories, not anything they did.
> "Speak ill of no man"
Aha.