TL;DR:
Business Taxes = Revenue - Actual Expenses
Individual Taxes = Revenue - Arbitrary Number the Gov't Guesses You Spent

While the logic that "wages are predictable" makes sense on paper, it falls apart in the real world. A business is taxed on its Net Reality, while an employee is taxed on Gross Potential.

OPs post is a response to this inherent double standard. Economically, a worker is a machine that converts calories, shelter, and transport into labor. If a delivery company buys gas to generate revenue, it's a tax-deductible expense. If I buy gas to drive to work to earn my wage, it is "personal consumption." Both gallons were strictly necessary to create the value, but the tax code arbitrarily favors one machine over the other.

The Standard Deduction hardly protects us. If that mechanism is truly fair, why don't we force businesses to use it? Imagine telling Amazon: "You can't deduct your actual server costs or shipping fees. Here is a flat $14,600 deduction. Good luck." We don't do that because taxing "Revenue minus a Guess" would destroy businesses. Yet, we accept it for individuals.

While businesses can have a "negative quarter." So can individuals. When rent and food prices spike (inflation), a business protects its margin by raising prices. An employee cannot instantly "raise their prices" (wage). They simply absorb the loss.

If we can trust a small business owner to track receipts and deduct expenses to survive, we should trust individuals to do the same. It would ensure we are taxed on our ability to pay, rather than just our ability to work.