Does performing the obligatory prayers in the Meccan Sacred Mosque expiate for abandoning prayers for the past 10 years, and if not, what is the solution?

Neglecting prayer out of laziness, while acknowledging its obligation, is one of the gravest sins. Some scholars have even considered it an act of apostasy that expels one from the faith. Whoever repents with sincere repentance, Allah accepts their repentance and replaces their evil deeds with good ones, as Allah Almighty says: "Except for those who repent, believe and do righteous work. For them Allah will replace their evil deeds with good. And ever is Allah Forgiving and Merciful." One should not despair of Allah's mercy, for Allah loves those who repent.

Prayer in the Grand Mosque has great merit and is equivalent to one hundred thousand prayers elsewhere. This is among the good deeds that expiate sins. However, this does not exempt one from making up intentionally missed prayers, even though some scholars have said that making up prayers is not obligatory for those who intentionally abandoned them; rather, they should increase their voluntary prayers and acts of obedience to compensate for what they missed.