Is anyone actually stuck on an old version of Rust

I really appreciate Rust's stability guarantees. I can happily run rustup update whenever I want, and I never worry about my code breaking, even at my job.

But recently, I had an idea to remove a function from a crate that I maintain, which essentially duplicates the recently-stabilized array::from_fn. But it occurred to me that this function might still be useful to people stuck on older rustc versions.

I've never been in a situation where I needed an older rustc version than the latest but I'm curious: are there any people in this situation? If so, what is blocking you from upgrading? Are there legitimate reasons why one might prefer to be on an older Rust version?

Thanks 😁