What that even means? Just random words. unsafe block is just an illusion and doesn't prevent any bugs. Don't get me started on the cult that shames repos that use it.
Sure, but upon review it was found some of the code was using unsafe without reason, and people submitted pull requests which made the code better. It's better because you are sure it doesn't have a memory unsafety bug, even if the code "looked" right before.
Given how Actix was used for benchmarking, I'd imagine that there was a reason the original developer wanted to use unsafe a lot. Nginx was written in pure C, and that is an act of wizardry. I can't imagine wanting to do any work for a language with a 'community' full of people eager to flame or do worse things to developers who don't meet their pompous definition of safety.