I do run into them even though I use Rust for ~3 years now, but only in non-obvious cases, e. g. when all references to the borrowed data are dropped before the end of the function.

There are also some reported issues that may be false positives, e. g. https://github.com/rust-lang/rust/issues/107115. In some cases, the error message can be misleading: https://github.com/rust-lang/rust/issues/112650