The translation is very misleading.
The Massoretic text (MT) is:
על כן יעזב איש את אביו ואת אמו ודבק באשתו והיו לבשר אחד
The first to words על כן mean "For that (reason)" or "That's why". In Hebrew they convey no sense of obligation or judgement like "Therefore" does ("Therefore you must...)".
The verb יעזב is mistranslated as a third person future with the unfortunate use of "shall" (as in "shall"/"shall not", which has no counterpart in the Hebrew text), but it is in fact an indefinite form that refers to men leaving home to marry in the past, present and future.
So the meaning of this verse to someone who is literate in classical Hebrew is:
That's why a man leaves his father and mother and sticks with his wife and they become one body."
There is no hint of any obligation or commandment in the Hebrew of this verse. This verse explains that the reason for a man leaving his father and mother is given in the previous verse.
In general you can't draw inferences or implications from translations. The translations give you only a general idea of the meaning of the text. To draw the inferences you really need to have a good understanding of the language of the original text.