TurboTax does not state that an ITIN is required. It is only required if they want to e-file their return with TT, as we don't support filing without one for an NRA even if they file MFS (and it is required if they file MFJ).
You can mail a return prepared with TurboTax without an ITIN. You just cannot file it electronically.
The W7 won't be rejected if you file MFS with your NRA spouse and send it in in order to be able to get an ITIN to efile the next season, which is what we usually recommend.
Including the W7 is for the convenience of being able to efile in the future.
As the IRS and tax laws change, TurboTax will make changes needed to stay current.
