Or maybe they think the Lib Dems will be better at fixing the potholes and gritting the roads etc?
Too much overthinking going on as a result of LE results as usual. There is a very good example right now re Ed Davey's speech banging on about the NHS and tax rates etc, not issues that were actually voted upon last night.
That's not really how local elections work in reality though, is it? Otherwise it would be a bit strange that people have suddenly decided en masse, across the country, that their Tory councillor is no longer up to it and would prefer the Lib Dem candidate.
You only need to read commentary from various party door knockers who are saying the key issues brought up were Boris, partygate and cost of living.
Whether it's right or wrong, national politics has a huge influence on the outcome of local elections, I'd say most people are more aware of what is going on in Westminster than they are their local council. I couldn't even tell you who my councillor is, or what party they represent.