If you want fast nix evals and docker builds, you absolutely do care about per-core performance.
I have little experience with Rust but, while I do know that it parallelises quite well, I also believe that there are still many single-threaded operations on the critical path though such as linking.
I think for your purposes, you'll do well with any 8-core AMD Zen4 that can draw more than 45W or any 4+n core Zen5. The latter would be a bit more efficient but practically the same perf in code compilation.
Intel is not competitive currently and ARM is still not quite there yet.
Please stop trying to interpret the SMART data report. Even if you're knowledgeable it can easily mislead you because this is vendor-specific data that follows no standard and is frequently misinterpreted by even the program displaying the data.
If the self-test passed, it's likely the cable or the controller. Try a different cable.