I somehow thought that IDA Free was missing the decompiler, but I just downloaded 8.2.221216 macOS x86_64 and while it did a much better job at identifying the symbols in the rust binary, regrettably it then consumed 100% of the CPU and effectively locked up. So ... better, I guess? :-/
Myeah, that sound like a bug in this variant. File a bug report with them, probably they'll release a better free one then you can properly test your theory. Good luck