I do think it can work from a gameplay perspective. I just think that in the Persona series, a series especially focused on treating people well and with respect, the relationships should portray healthy, green flag, nontoxic relationships. This becomes harder to justify when you do it for every female character, resulting in pretty effed up power dynamics like the Kawakami one (I personally find the Futaba relationship a little suspect, myself). I also expect the writing staff to put less effort in if they're expected to write a bunch of highly generic, structured relationships, versus if they were to do just one.
In a real dating sim I'm not going to have this issue.