It's not they can't, but they won't.
Am Not sure what you are trying to defend here. Are you denying that LO's dev designed what on my list, so they can sell the cheat better?
I'm solely calling out that practice. Not against LO's dev.
There's nothing wrong when the dev choose to better monetise their game, as long as it doesn't affect the actually gameplay. And even when it does (like LO and Tavern of Spear), if the game itself is good, people can overlook that.
It's a delicate balance when indie dev's going this direction.
And mind you there's no shortage of devs go too far into anti-player direction (like Hornstown, ToS)
I'm not really defending anything, I just disagree with your conclusion that the game was designed with charging for cheats in mind. The cheats were only added half a year or so into the development, and a lot of the features like adjusting relationship points weren't added until much later.
I also just don't that the game has complicated or inconvenient mechanics. The relationship system, for example, isn't complicated at all, you just get or lose points based on dialogue choices or certain actions, which is something literally any VN does. Some of the RPG mechanics were poorly designed at the beginning, like the high exp requirements and slow character progression, but they were adjusted with future updates, which I don't think the creator would have done if they wanted to push for cheats. Iirc, some of the material requirements, like the scrap needed to repair the ship, were also lowered with time. I will give you, though, that it's time consuming and not very convenient to change the respect level (probably, haven't really needed to do it before, but I feel like you could maybe adjust it by working part time at the club or repeating certain dialogues?).
Anyway, I don't disagree with you that this practice exists, it is definitely the case with some games. Hornstown is a good example, paying players have a vastly different experience than f2p ones. I just don't think this applies to LO, but we can simply agree to disagree here.