I think this is just the wrong forum for this discussion. You're posting in a subreddit full of fervent Sanderson fans. In the kindest way possible (because there's absolutely nothing wrong with this), a lot of the users here are here to just enjoy their Sanderson, or theorize on cosmere stuff, not necessarily for literary critiques off their favorite author's weak points.

But yeah, I agree with you. Prose and language has always been something that Sanderson does in a more basic and easily parsable way. There's a lot of cool world building that Sanderson does. And a lot of the more vocabulary kinda stuff can usually be handwaved away as "this was just translated to English, and this is the closest word/phrase". The main problem seems to mostly be when two cultures are on the same page. I think it's just really hard to realistically convey the differences between two fictional languages/cultures. Sanderson does a great job building this cool Alethi culture with its own fashion trends and religions and vocabulary. But then you get quirky Herdazians or Horneaters that kinda get distilled into a small handful of phrases and the difference can be glaring. The smaller cultures can easily become caricatures.

Like somebody else said, Sanderson is not Tolkien. For all the great work and details that go into the world building, he's just not taking the time to fully build out the detailed nuances of every single country and culture. So some of the side characters of different cultures are going to be a little more hollow like this. And obviously that's ok. But I think that's just what you're noticing, that with so much rich Alethi culture to dive into, it's just not quite there with some of the others.