The LSP support for Rust has trailed JetBrains own Rust plugin, which has long since morphed into the language-specific IDE, RustRover.
RustRover has the best AST suggestions and refactoring support out there. It works in gigantic workspaces, across build scripts, proc macros, and dynamic dispatch.
The problem with RustRover has been the lackluster AI support. I've been finding AI autocomplete generally much more useful than AST understanding, though having both would be killer.