I do seem to recall that in 2019 it was the opposite, conservatives only got a small bump from the previous election but picked up a lot of seats because of a labour/lib dem split
looking around the map I was thinking "is there anywhere Labour got an outright majority"
Then I clicked on Merseyside and Central London "oh yeah"
To my American brain all I can think is "why aren't Labour and the Lib Dems 1 party?" since in our world, they're both the Democrats
Lib Dems sat in government with the Tories in 2010, so in I'm not sure they would necessarily fit in with Labor. Maybe more so since Brexit, because the UK got a kind of American polarization around leave/remain
when you read their platform (well the condensed version on their website) the definitely would.
also the sorts of people I knew who voted lib dem (granted in 1997) would 100% be voting for Democrats in the US. (anecdotal, I know)
I think the LDs learned a painful lesson about the tories.....
(The cynicism arises IMO because parties more regularly break their implicit promises: the Liberal Democrats implemented most of their manifesto 2010 to 2015, but they had spent a decade implying they were to the left of Labour, so people felt betrayed.)