Answer

There are several kinds of statements like these. Some are claims about the Holy One’s attitude toward human actions. In my view, these are a kind of exhortation and encouragement to act properly. Instead of saying, “Act in such-and-such a way,” they say that whoever does such-and-such, the Holy One, blessed be He, does XYZ for him (ties crowns for him, gives him a male child, and so on). No person can really know what the Holy One does for someone, and so in my opinion that is the meaning of these statements.
Someone who lives in a large city and does not sin—that is a virtue that anyone can understand. What they attach to it is already a matter of rhetorical flourish.
But even if you take these statements as factual claims, you have to understand that they are not supposed to be fulfilled in every case. Rabbi Elchanan Wasserman gives the example of: whoever recites havdalah over a cup of wine will have male children. If you recite havdalah, that gives you merit for male children. But there may be opposing considerations because of which in the end you will not receive male children (for example: because one is not careful with vows, his children die). On this logic, see my article on the ukimtot:

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