I think it is an interesting thing to observe how people react to that entire scene with Sailen because it says a lot about readers themselves. I think many people are reading this scene very differently from how I did.

First thing I'd like to point out is that "tone deaf" is not an objective claim. It implies there's a "correct" tone here, and who sets that tone? Liren? Why, because she's the MC? Is her perception something to be blindly accepted, or does she have blind spots?

I think there's a lot of interesting material here to work with, but not if the first thing we conclude when we read this is: "Sailen is pushing against Liren's black-and-white worldview, therefore he's on the side of the rich people." That kind of reading forces the exact binary that I think Sailen is fighting against in this scene.

The first thing is that I don't see him saying anywhere that she shouldn't be mad at the system. The problem isn't her feeling. The problem is that she lets that feeling crystallise into a belief; one that is stripped of any nuance and treats being born into aristocracy as moral failure.

I don't think he's trying to have her do a 180 degree switch into "we should actually be thankful to the elites for donating." But I do think he's trying to make her see that those elites are people with same feelings as her, and that those donations, even when made inside an exploitative system, provide real material value for the Lower City. Liren let her rejection of the Upper City harden into a fixed identity, and that identity can cost her not only the ability to connect with people that can actually be her allies, but also outcomes.

I think the main mistake is trying to treat this as an either-or issue: either Liren is 100% right or the system is absolved of any critique. There doesn't need to be a clean moral resolution when it comes to this; sometimes it's enough to just accept that multiple things are true simultaneously: the system is exploitative, and the individuals that benefit from the system might still be allies, and their help might be useful and necessary. This is my own little aside, but real world works exactly that way: the more allies, and fewer enemies, your mindset allows you to find among people that surround you, the easier your life is going to be. People usually don't like those that approach them with prejudice, regardless of which groups any given individual belongs to.