Loyal Jew:
takah, I base it on the first rule of tznius: don’t show yourself off in public.
When you can quote a real source, not something you made up, then we’ll talk.
Driving is hardly “showing yourself off in public.” Do you hold that women should never leave the home? Should they never go to shule? How should a woman work to support her husband in kollel if she can’t drive – should her husband miss learning time so he can drive her around? Should she waste tuition money on taxis?