No, that is not correct. A 2017 (twenty seventeen) tax return can *never* be e-filed. Not ever. The IRS closed e-filing for the 2017 tax filing season on Oct 15, 2018. It is closed permanently and forever. A prior year tax return *must* be printed, signed and mailed to the IRS. The IRS says so.
your reply was not totally accurate perhaps it is the case for turbo tax.
Any individual is able to file an electronic tax return and the IRS will accept an electronic tax return for the prior three(3) years as long as you have the correct software (H&B Block, Liberty and your regular CPA and EA) normally work with much advanced software's that are geared toward accountants.
Prior year returns can only be filed electronically by registered tax preparers, and only when the Modernized e-File System is available. The IRS posts the status of the Modernized e-File (MeF) system on the MeF Status Page. Individuals filing their own prior year return must print/mail the return.
So it's not a TurboTax thing. It's an IRS thing.