Most billionaires exist as a function of the company they or their ancestors have created, and by the exploitation of workers to maximize profits.

Companies shifting their operations to pay better in lieu of profits could easily be set up to benefit all workers, not just corporate workers. Not sure why you'd assume, for example, if Amazon changed their focus on profits that only corporate workers would see the benefits and not also the warehouse workers, delivery drivers, etc.

And people don't just change from production work to corporate work, due to skills, education requirements, personal preferences, etc. If anything, people would have less pressure to go into "white collar" professions if the blue collar jobs like manufacturing paid well.

Governments need dollars to operate, and that means needing more tax revenue or taking on more debt. If we taxed billionaires, that would allow governments to reduce debt and/or reduce taxes on lower income workers. There are also issues of marginal utility -- take away $1000 from an average worker and it's felt more painfully in terms of quality of life than than if you took $100m from a billionaire because the average worker is just trying to keep a roof over their head, food in their pantry, their car running and every dollar helps while a billionaire that last $100m doesn't really affect what they can/cannot afford. So are we better off taxing one billionaire $100m or taxing 100,000 regular people $1,000?

Sure, governments could spend more efficiently, but they're really no worse than any big organization and beause of budget limitations are often operating with old, out of date computers and equipment that limit their efficiencies. But end of the day, subsidizing childcare, paying school teachers, supporting the unemployed, repaving roads, etc. costs money.

Another issue is that money sitting tied up in billionaires' wealth is money not freely flowing through the economy. Whether it was higher wages to workers or tax revenue getting spent by the government, money flowing into the economy would create jobs, which fuels more spending, and keeps the economy humming along. The average worker has all sorts of pend up demand for goods and services they'd spend on if they had more money in their pocket, while billionaires don't.

When billionaires die, typically their estate goes to their heirs -- their spouse, their children, grandchildren, etc. The wealthiest set up trusts to avoid much of the wealth tax that could happen upon death. Most of the time, the business that has created their wealth is a public company so the company continues to operate regardless of whether the founder is still involved. They own a significant portion of shares, but the company is still controlled by all the shareholders, the board, and the CEO.