Not exactly a lie so much as misleading.
Yes, the lowering of prostate cancer risk does, in a sense, compensate for the increase in breast cancer risk, in a sense. That is, your overall cancer risk is more or less unaffected because you will have a higher risk of breast cancer than before but a lower risk of prostate cancer.
However, that doesn't mean you shouldn't worry about breast cancer. Like any woman, you'll need to be screened periodically, especially as you get older.