Why do most Islamic countries not apply the Quranic rulings concerning the cutting off of the hand of the thief and the lashing of fornicators, while the demand for equality in inheritance is objected to on the grounds that it violates a Quranic text, even though the Quran is valid for every time and place?

There is no difference between the ruling of the Quran regarding inheritance and its ruling regarding the punishment for a thief. All of its rulings are truth and must be acted upon. The sin of abandoning a part of the truth does not mean completing the error by abandoning what remains. Rather, one must strive and work to implement what has been abandoned, like someone who fasts but does not pay Zakat; he is commanded to pay Zakat, not to stop fasting. The Prophet, peace and blessings be upon him, informed us that the loosening of the bonds of Islam begins with governance, then prayer.