Why is Rust rarely used for web server backends?

I've used Rust for some small projects and find it high-level enough for any server-side logic. You wouldn't have any issues counting shopping carts or handling other typical tasks.

Also, its package management is great - no node_modules or virtualenv hell. So, it seems like we could use Rust for most backend code (except for ML, for obvious reasons).

At the same time, I rarely see companies building web backends in Rust. Many still use PHP, Node.js, or Python. This seems strange because if a Rust program compiles, it's almost certain to work, which isn't always the case with other stacks.

I'm asking this because I work as a Node.js backend developer, and I actually see no problems with using Rust instead of Node for my job.

Are there specific hard problems I'm missing as a beginner that keep Rust in more niche roles and prevent its adoption for mainstream web backends?