Khandro, you’re all over the place with this – jumping from one thing to another – and, as I demonstrated, you introduced God to the discussion.
//'Which would you prefer to be, Voltaire's, troubled, unhappy Brahmin, or his untroubled, happy, washerwoman?'//
Neither. I can’t imagine myself in either situation. Unlike the Brahmin (who actually doesn't seem too smart to me), I have never regretted seeking to educate myself, it has never made me unhappy, and I would never consider it wasted time - and unlike the old lady, I am not ignorant.
With regard to your original question, since Voltaire’s old lady wasn’t capable of considering the wonky concept of ‘non-provable truths’, I don’t think this story is a good illustration of what you’re asking – which as far as I can tell is ‘is self-delusion bliss?’ Had you omitted the ‘non-provable truths and untruths’ bit, the story would have fitted and you could have simply asked ‘is ignorance bliss?’ – but you didn’t.