Is the verse: (And whoever turns away from My remembrance – indeed, he will have a harsh life), and similar verses, to be taken as general, or are there exceptions?

The correct interpretation of the verse is that "a constricted life" (al-maishah ad-ḍank) encompasses every person who turns away from the remembrance of Allah, proportionate to their turning away. This is not exclusive to the torment of the grave but includes the servant's life in this world, the Barzakh (interim period), and the Hereafter.

Regarding those who claim that disobedient individuals and disbelievers enjoy a life of ease, the response is that this does not negate the constricted life within their hearts, characterized by alienation, humiliation, and regrets. Rather, the intoxications of desires and the love of this world conceal this from them. Therefore, "a constricted life" is inevitable for anyone who turns away from the remembrance of Allah in their worldly life, in the Barzakh, and on the Day of Judgment. The heart finds no stability, nor does the soul find tranquility, except through Allah. He whose eye is content with Allah, every eye becomes content through Him. And he whose eye is not content with Allah, his soul is torn apart by regrets over this world. Indeed, Allah has ordained a good life for the believing doers of righteous deeds, both in this world and in the Hereafter.