Good analysis
The problem is differentials one jump up the ladder
At the bottom of the heap the non productive permanently on state assistances of varying kinds.
Then those who work for sub optimal pay and conditions
Think Zero hour , Uber , Deliveroo the gig economy
Then we have the permanent posts but wit no pensions holidays entitlements often short renewable contracts to avoid such costs
Then have permanent but low paid who will be loyal as any pension, benefits , childcare, oncome security is better than nine.
While this thread looks at UK , In USA health benefits are a major anchor
Some are in tied housing in hotel domestic agricultural and pub work where no job means no home.
Next tier are those with skills who have enough leverage to strike with skills that require training and or diplomas to be insure like Teachers Pilots, Train drivers Drs or Truckers
The longer and higher the entry bar usually the better package .
The old adage the guy cycling to work in the rain is not a dentist