Turbotax manifestly does not follow IRS guidelines for NRA spouses who neither need nor require an ITIN. The guidelines state explicitly to enter NRA in the SSN field for the NRA spouse in this case, which your software is incapable of doing, a bug or deficiency you are unwilling to fix. The workaround you describe is a kludge; what's more, it requires the filer to file by mail, which the IRS expressly advises against because of the inordinate delays in handling such returns, given the global pandemic of COVID-19.
Users should be aware that, whatever it shortcomings, TaxAct correctly handles the above case and will e-file married-filing-separately returns with NRA spouses without an ITIN.
