While U.S. income tax filing is a perennially popular topic on HN, I don't recall seeing mention of the free, human-assisted (by trained volunteers) filing that has been provided under IRS sponsorship for decades[0]. AARP TaxAide[1] is also a large sponsor. I have been a volunteer in the past, and can report that in at least some locations, there is no $64K income limit, but it is true that a number of "complicated" forms can disqualify use (such as depreciation expense deductions).

Having the option to sit face-to-face with another person who can answer questions about your situation at no charge is of value.

[0]https://www.irs.gov/individuals/free-tax-return-preparation-...

[1]https://www.aarp.org/money/taxes/aarp_taxaide.html