I understand what you mean but "pay it once" is the wrong description for something that you do hundreds/thousands of times per day as a developer. Every time I save a file in my IDE, the Rust checkers run and are very slow.
This means rust analyzer and your IDE will have different target dirs (target/debug and target/rust-analyzer), this can prevent flagging resulting from cargo and rust-analyzer fighting over the features etc. I have this set at system/global level in my IDE config. The downside is that you'll use double the disk space.
I have a backend and frontend for my project, and the typescript frontend with its sub-second feedback cycle definitely helps for staying in a flow-state. With all of the improvements above, rust is still at 3 to 10 seconds.