The problem with taxing the rich very highly is that not only are they very mobile, but there are actually not that many of them. You can get more tax in by adding 1p to income tax or VAT than you can get by adding 25p to tax rates for the highest.
I am looking at taxation as a redistributive measure, MOnica. The amount of additional tax revenue this might or might not add to the national 'income' is completely irrelevant. And you said yourself that the extra tax that high earners might contribute is 'negligible'.
There are 31 million tax payers. in the UK and the starting salary to be in the top 1%, 310,000, is a salary of £160,000 [[www.thisismoney.co.uk/money/comment/article-7357395/Who-1-Britain-one-them.html ]]. The majority of people in this group will earn under £250,000. The number of people with enormous incomes, £1 million+ is probably less than 10,000. Even if they all paid £100,000 more tax, it would only bring in £1 billion, negligible in the nation's finances.
By the time most of them have relocated to other countries, the amount would fall even further.
Firstly, I'm sceptical of the relocation argument. Are you saying that they will all nip off to other countries and be able to take equally high earning jobs there? I find that a bit unlikely.
Secondly, if they do go, they are not irreplaceable. While free market adherents might try to argue that they have special talents that deserve very high salaries there are equally those who would argue that they are not necessary to a company's performance.
Both viewpoints are represented in this article:
www.bbc.com/worklife/article/20210125-why-ceos-make-so-much-money
I did say that I liked your suggestion that executive salaries should be raised by the same percentage as that of company workers. Definitely an equable proposal.
As far as distribution is concerned, I think we really have to look at the source of people's wealth. Leaving aside inherited wealth, we have to ask where the money is coming from to pay these inflated salaries and to pay dividends to investors, who not only pay less tax on them than people pay on earned income, but who are, in the main, already wealthy.
It is pretty clear that the source of these payments is the company's profits. In which case we have to ask, what is the source of the company's profits? and the answer will be, the company's customers. Ultimately, these customers will be the general public, or the state. (tis might be somewhat indirect in the case of companies which supply to other companies, but the money they charge their customers is accounted for in the price of the customer's finished product, sold to the public or the state)
So, it is our money, either from our earnings or from public money, that is creating those profits. If these profits aren't recirculated into the economy by paying workers sufficient not only for necessities, but also for the extras, hospitality, holidays, hairdressers, hobbies etc. then it is being sucked out of the economy by the already wealthy who don't spend enough into the 'domestic' economy to sustain all these small businesses supplying goods and services to the less well paid, and which are the lifeblood of the domestic economy.
Progressive taxation isn't necessarily 'taxing the rich very highly', it is putting them on the same tax footing as the rest of the population so that they pay the same percentage of tax on their incomes, from whatever source, as does the rest of the tax paying population. Which they don't at the moment.