Is it true that the reward for a Sunnah in Ramadan is like the reward for a Fard, and the reward for a Fard is seventyfold, as narrated by Al-Bayhaqi in Shu'ab Al-Iman?

The aforementioned Hadith was narrated by Al-Bayhaqi and Ibn Khuzaymah, and the Huffaz (Hadith masters) have judged it to be weak. However, scholars have permitted acting upon it in matters of virtuous deeds under specific conditions.