The great Lib Dem curse is that they were an unusually effective junior partner to the Tories - low drama, coherent agenda, highly managed expectations. So, in the age of diminished trust in consensus elites, they are the seen as the ultimate party of consensus elites.
That points to your broader thesis - the public wants someone chaotic to shake things up. That was certainly the case with Johnson and continues to be the case with Farage and Polanski is perhaps an even purer example than Farage.
The cynical take is that a lot of would-be voters know that they wouldn't be happy with a Farage or Polanski government any more that they were happy with a Johnson government. But they feel it would make a lot of elites even more miserable (grievance & resentment), which seems to point to a prolonged future era of bad governance.
But there's also a constructive take, which is that institutions and their policies have outrun public permission and mandate - that nothing answers to public opinion and that bringing in Farage or Polanski would restore that accountability. Trump in the US has shown there's an element to truth to the basic MAGA/Reform allegation that much institutional function, governmental and NGO, is ideological patronage and clientelism - it rewards one side - the omnicause industrial complex - and punishes the other. So, they do have a point there. But there's also a high degree of fantasy: Trump is neo-liberalism, global elitism on steroids - muscular, aggressive, impulsive, and somewhat stripped of its high-minded rhetoric, but not much different in its aims and means than Nixon, Reagan or Bush (or even carter, clinton and obama)
This is where much of Reform and all of the Green agenda crashes onto the rocks: neoliberalism is the only game in town - world financial markets, global trade, digital media, global cultural, global energy flows. There simply is no other plausible configuration that's being presented. For all of Trump's efforts on tariffs (in a country that could plausibly introduce autarky) the effect is that not even one net, new factory has been built in the US, i.e. increased input costs for manufacturing have entirely offset tariffs applied to finished goods. He has reduced legal immigration by 50%, a titanic change, but that's hardly bringing it to zero - and with enormous industry efforts to carve out ever more exceptions to fill research universities and high tech startups, and to pick agricultural crops - pressure that will only grow as these are strategic concerns - again the inexorable pressure of the neoliberal order.
My own views is that it's imperative to reevaluate civic institutions to make them fit for purpose, its unfortunate that Reform is the only one serious about it. There's also a great need for deeper thinking about the neoliberal order that we live in and realistic ways that its harms can be mitigated, and also imagination about what alternatives might exist. But instead all the left produces is age old fantasies that have already been shown not to work while the right engages in slights of hand to pretend they're not implementing neoliberalism when that's exactly what they're doing.