I think Reform and similar are often home for protest votes when people are tired of the mainstream parties. I don't think people necessarily vote for things in an election that they might ostensibly voice limited passive support for. Not in large enough numbers under FPTP anyway.
I would agree. Easy to express dissatisfaction by telling a polling company something but very different from putting an "X" next to the unproven candidate with rather extreme policies many of which you don't actually agree with. I don't think Council elections necessarily provide a good indication given how much of Council "policy" is just in deliverying routine services you don't actually think about much as they just happen.
Plus we are a long way from any likely election. Many of Labour's failings are not too hard for them to sort out if they can get some find some sanity and some better people in post (which they have not done so far).
In some ways a but like the French Presidential elections almost always take 2 rounds. 1st vote and people tend to vote more radical and when the result is announced and some extreme candidate gets into round to the electoraterecognise what a close-call they almost created and sanity returnsfor the 2nd round.