Is the saying: "Whoever sincerely wishes to do good, Allah will grant him his reward; for in the Hadith, it is stated: 'One with a sincere intention says: "If I had wealth, I would do what so-and-so does," so he is rewarded according to his intention, and their rewards are equal'" correct? And would wishing to do the work of the calligrapher of the Mus'haf, Uthman Taha, earn the reward of everyone who reads the printed Qur'an?

The message you received is entirely incorrect. Merely wishing for good is not a sufficient reason to earn reward and recompense. Rather, there must be a firm intention to obey. If a person is unable to perform an act of obedience due to an impediment, then they receive a reward similar to that of one who performed it. Many texts indicate that whoever sincerely intends to perform an act of obedience, and is then prevented by an irresistible impediment such as incapacity or inability, attains the reward of the one who performs it, and perhaps their reward is even multiplied. Among these is the saying of the Prophet, peace and blessings be upon him: "The world is for four types of people: ...and a servant whom Allah has given knowledge but has not given wealth, so he is sincere in his intention, saying: 'If I had wealth, I would do the deed of so-and-so'; he is by his intention, so their reward is equal." However, this reward may be in the basic recompense and not in its multiplication, unless there is a real excuse and an irresistible impediment preventing the action.