Benchmarking strings is often benchmarking memory allocation speed or the GC.

If you manipulate strings day in day out in your workflow, the first thing you do is remove all those allocations and for what is left you use a memory pool.

The speedup could easily go into the 20x in any language. It's actually one of the area where Python or JS can beat statically typed languages, they focused a lot into optimizing strings while statically typed languages often leave that as an exercise to the reader.