It's about execution when it comes down to that. The key criterion, IMO, comes down to the word 'senseless' and how context justifies 'senselessness'.
Does said work handle problematic topics/content well? More specifically, does it indulge in the problematic stuff? Does it have something to say about the issue(s), or does it provide a new perspective on it/them? Does it contextualise them in a realistic way?
(Of course not everything has to, especially works which are lighthearted or have a lot of levity.)
For instance, that massacre game. What's it called. "Hatred"? IIRC it did critically badly because it didn't have anything new to say and just indulged in senseless behaviour. But plenty of games with violence do not indulge in the senselessness. Some do - and again, that's fine if executed right- instead they contextualise it and make it part of their narrative. That's an important part of Western action games: contextualising the violence. In your example, imagine a game adaptation of American History X where we play a white supremacist. Even if we only played the home drama bits. That would be saying something about white supremacy, and when the player is forced to attack his sister, the violence would be contextualised and have a dramatic purpose.
A big problem I have with Japanese content which is heavily sexualised is that it often is not contextualised at all and it becomes senseless. This is also true of violence in many games. I couldn't get past the openings of several anime and videogames because pointless sexy bullshit happens. (We don't know if this is true of Summer Lesson yet.) Compare that to The Witcher 3 where you can play the entire game without a proper sex scene (just some dream-scene nudity at the opening), and when it does happen, it has hours of context beforehand imbuing the sexiness with justification and meaning. (The sex scenes are executed awfully but that's a whole other thing.)
And it goes both ways wrt violence: Similarly, there have been a few videogames (like Postal) that I couldn't get past the opening of because the violence was so senseless. The problem works both ways.
OP seems to have a problem with Summer Lesson - which I can empathise with - but just doesn't have enough information and is making some leaps. We don't know whether it's relevant. The release of the game will tell whether they succeeded or not.