The author seems to mostly be talking about the aliasing rules, but if you don't want to deal with those, can't you use UnsafeCell?
Imo, the more annoying part is dealing with exception safety. You need to ensure that your data structures are all in a valid state if any of your code (especially code in an unsafe block) panics, and it's easy to forget to ensure that.
For those saying unsafe Rust is strictly safer than C, you're overlooking Rust's extremely strict invariants that users must uphold. These are much stricter than C, and they're extremely easy to accidentally break in unsafe Rust. Breaking them in unsafe Rust is instant UB, even before leaving the unsafe context.
This article has a decent summary in this particular section: https://zackoverflow.dev/writing/unsafe-rust-vs-zig/#unsafe-...