@maxxcan In the most extreme example, you could take the wealth of billionaires in the UK and give everyone a +20k pay rise - for 1 year.
1 year, because after, the billionaires will move all of their wealth and assets overseas (it's called capital flight).
When you look at tax statistics, in most western countries, the very wealthiest pay a huge portion of the tax burden.
Hiking their taxes would only send the signal: this country is not open for business. GDP and tax revenues would plummet.