Good question! There's no single thing, I think, and the things I dislike about it aren't even really technical criticism or the like. They're more... aesthetic? I find the syntax unpleasant, for instance. It's extremely opinionated and a few of those opinions are ones I disagree with.

Also, just generally, it tends to make even simple things pretty complex. I understand why and am not really objecting to that, but it does make using it a bit like running with lead shoes.

I expect that the latter part may get better as I use it more (but perhaps not -- there are other languages I'm fully competent in but dislike for similar reasons).

I share your sentiment about Rust. Fine language for sure, I just don't enjoy programming in it. Simply put, I don't like using the abstractions that the language encourages.

For what it is worth, I found pursuing Zig to be a breath of fresh air. It's a promising alternative in the same space as C (and also Cpp and Rust). Checkout Andrew Kelley's introduction to the language.

Which opinions do you disagree with? For transparency, I tend to find myself agreeing with almost all of its models/abstractions.

There are a few, and they aren't something that I can't live with, of course. A great example of the sorts of things I'm talking about are Rust's insistence on camel case and snake case.

You can turn off certain linting rules in the global cargo config, but yeah I don't see why camel case shouldn't have capitals etc. either.

edit: Whoops. I mean snake case.