Last year, if you had multiple sales of capital assets but did not report them individually but reported a summary of the sales on the filed 2022 tax return, then you would have been required to provide the IRS a Form 8453, U.S. Individual Income Tax Transmittal for an IRS e-file Return and a Form 8949, Sales and other Dispositions of Capital Assets for the individual sales.
If you did not have any sales of capital assets in 2023 or did report the individual sales of assets on the 2023 return using Form 8949 and Schedule D, there would be no need for you to provide the Form 8453 and Form 8949 to the IRS after the 2023 tax return was filed.
The Federal Filing Instructions would have noted this if you were required to provide those forms to the IRS after the 2023 return was filed.
This sounds like you received the TurboTax email or message in error for tax year 2023.
