For seniors over 65 social security can still be taxable but new tax deductions will apply.
For 2025, the total standard plus bonus deduction for those age 65 and older is $21,750 for a single person and $46,700 for a married couple filing a joint return. However, income thresholds apply. While the taxable portion is added to your total income your adjusted gross income will be much lower resulting in lower tax liabiliy.
It won't change the taxable amount of your SS or your AGI. You will get a 6,000 (12,000 if both over 65) deduction off the AGI which will reduce your taxable income. It is phased out if you make over 150,000 married or 75,000 Single. It is in addition to the Standard Deduction (or itemized deduction). See this post for more info