I think the big problem is that politics is now a profession. Most of those in high places in politics have been at it man/woman and boy/girl. Few if any have any life experience outside politics.
In the past there have always been professional politicians (read the novels of Anthony Trollope) but the majority of MPs have come to politics after decades doing other things. Some of them have been the local squire or union apparatchiks (excuse spelling) but all of them have brought an experience of lives, professions and regional experience completely lacking in most of today's politicians.
Not only have today's politicians only ever worked in politics their friendship circles are all political. Once again in the past MPs had hinterlands. The labour MP was down the pub in the constituency with his mates, most of whom continued to work in the factory or works where he once worked. The Tory landowner or mill owner knew about their industry whether land-based or industrial. Their friends and associates were more likely to be fellow landowners or working industrial or professional. Given that all politics is self interest, Tory or labour, they did at least know what they talked about when they rose in the House to talk about agriculture or industry, even defence or education because they were grounded in their locality and constituency and had their fingers on the pulse of their constituents.
I do not see how any change can be effected unless we can deprofesionalise politics. How I am not sure. Limit MPs to two terms in Parliament unless selected for a cabinet position? Make 35 the youngest age for serving in Parliament? Insist that every candidate provide evidence of 10 years working right outside politics (that would exclude those working for political PR companies, lobbying companies and the like)? Make MPs come up through local politics - 10 years as parish/district/county councillors?
I honestly do not know, but I do think for most MPs it would help if politics was first their hobby, not their profession. An MP should define themselves as a software developer and MP or doctor and MP, but their definition should be first their profession.
My MP is a professional politician. I have no idea whether he ever has ever earned his living any other way.