You keep using that word, but I don't think it applies here. Just because the reasoning behind a design choice isn't immediately clear, doesn't mean that there is none. From my point of view, all the supposed arbitrary content gates have to do with who you favor in a more emotional manner, those being, do you trust Maxine or Lindsey, do you treasure Jacklyn or Flora, do you side with Isabelle or Kate, and such. This intention was made abundantly clear with Flora since the first decision, her strife being you spending time with someone other than her, later being reinforced in season 2 when she finally confesses to the player she wants to make things more serious only after she realizes the player may go out with Jacklyn and lose him, a sentiment shared with the mc.
The way I see things, these choices aren't useless, they're crucial to the plot and characters and enhance them. Kate and Isabelle's rivalry wouldn't be as strong if the player couldn't choose who to side with. Flora's forbidden love with her brother housemate wouldn't be as intense if there weren't options to be "normal", you with Jacklyn and Flora with the jackass with the BMW. Maxine and Lindsey... I'm not quite sure where the writer is going with this one but this one plot line seems to be still pretty raw considering last update was all about Lindsey's mystery, so I'm giving them the benefit of the doubt.
Now, this is all speculation and I may just reading too much into things. Me giving supposed reasons for the gates has the same weight as you not seeing any reason, which is none as we are not the writer and can't know the intent or lack thereof. But I personally have a little more faith in this game's writing than I do most others in the site.