Many people (accountants and lawyers) are employed or have their own businesses doing either corporate or individual taxes. If all tax loopholes are closed, tens of thousands would lose their jobs. Unfortunately, it just won't work. Now if you wanted to try to phase it in, you might het parts of it enacted, but there are real logical impediments to passage.
Workers all across America and across multiple generations have been disrupted by this or that change. Aerospace and farm workers, telephone operators, automotive workers, bank tellers, even going back to blacksmiths and buggy makers.
Books will still need keeping, dollars will still need investing, state taxes will still need doing. There will be plenty of opportunities.
Those tens of thousands should not treated like a protected class while hundreds of millions of others suffer the ill effects of the current code.
You forgot to add that the invention of ATMs and airport E-tickets is the cause of today’s high unemployment.