A more thorough explanation:

The Tax Cuts and Jobs Act of 2017 (TCJA) is a set of changes to the tax code that were signed into law by President Trump in 2017. The changes affected many areas of the tax code, including corporate tax rates, standard deductions, and estate taxes. Some of the changes were permanent, while others will expire by the end of 2025.

For individual tax deductions, the TCJA reduced some tax rates and changed many deductions. The seven tax brackets were reduced, and the income levels for the brackets were slightly increased. The standard deduction was greatly increased, which reduced the number of people who benefit from itemizing deductions. The deduction for interest on home mortgages and equity was altered, and the state and local tax (SALT) deductions became capped at $10,000. Miscellaneous tax deductions for things like workplace expenses for employees were completely eliminated. All of these changes will revert back to their pre-TCJA provisions after 2025.

• Before the TCJA, the highest tax bracket for individuals was 39.6%. After the TCJA, the highest tax bracket was reduced to 37%.
• Before the TCJA, the standard deduction for individuals was $6,500. After the TCJA, the standard deduction was increased to $12,000.
• Before the TCJA, there was no cap on the SALT deduction. After the TCJA, the SALT deduction was capped at $10,000.

These examples illustrate how the TCJA changed individual tax deductions by reducing tax rates, increasing the standard deduction, and capping the SALT deduction.

For businesses and investors, the TCJA greatly reduced the corporate tax rate, changed flow-through taxation, increased depreciations, and made fundamental changes to taxing international income. The corporate tax rate was permanently reduced to a 21% flat tax rate from 35%. Individuals were given a deduction of 20% from pass-through income from business entities like partnerships and LLCs. The TCJA enacted a 100% bonus deduction for business assets purchased through the end of 2022 and increased many expensing provisions that phase out after 2022. Lastly, the TCJA implemented major changes to how corporations were taxed for international income, including exempting foreign earned dividends from U.S. income tax for those owning over 10% of the foreign corporation and other provisions to tackle base erosion.

• Before the TCJA, the corporate tax rate was 35%. After the TCJA, the corporate tax rate was permanently reduced to 21%.
• Before the TCJA, there was no deduction for pass-through income. After the TCJA, individuals were given a deduction of 20% from pass-through income from business entities like partnerships and LLCs.
• Before the TCJA, there was no 100% bonus deduction for business assets purchased. After the TCJA, a 100% bonus deduction was enacted for business assets purchased through the end of 2022.

These examples illustrate how the TCJA changed business and investor taxes by reducing the corporate tax rate, providing a deduction for pass-through income, and enacting a 100% bonus deduction for business assets purchased.