How can you conclude that a 'significant proportion' of lecturers are unhappy, when in fact the names mentioned could just be due to one faculty?
There is a lot of variation between faculties and subjects for the same university. Whether you like it or not some subjects are more financially viable than others.
International students (who pay up to triple the fees of home students) for example tend to pick the same few subjects.
Went I went to LSE for example the number of students paying international fees for moneymaking subjects like Accounting and Finance was above 50%. For international relations... less than 10%. The international fee at that time was double the home fee and increased by 5% every year while the home fee was fixed.
That was before we get onto the subject of grants, corporate consulting/partnerships, etc etc.
I agree that universities are money grabbing and certainly people at the top are being paid loads but that's not the full picture. As funding is being rolled back (especially now that we're out of the EU) every department has to fend for themselves. The financially valuable ones even if they wanted to can't subsidise the others to the extent that's required... why would they?
Universities are expensive. Especially with the amount of babying and 'every student graduating' that we have in the UK. Places with free universities have tough weeder exams in second year, you are expected to work for it, they don't want everyone having a 'degree' for the sake of it.
https://www.statista.com/statistics/1084737/eu-28-adults-with-tertiary-education-attainment/
Even among the EU we have one of the highest educated populations, but this doesn't distinguish between locally educated British citizens and people with a degree who have migrated here.