FWIW I’m super supportive of bump allocators and arenas. I just don’t find this particular analysis compelling or sufficiently informative. YMMV.
I could perhaps be convinced that modern GC are super fast. But in hindsight your blog post is intended to preach to the choir and not change the minds of non-believers. If you ever write an apologetic I will gladly read it. It needs to be a holistic analysis of memory operation cost across all threads.
Bolz's blog post is not written to persuade anyone but to provide objective, verifiable information from which people can form their own conclusions.
I agree that a holistic analysis of memory operation cost across all threads would be not only more persuasive but more informative. But it is also much more difficult.
Unfortunately I appear to lack sufficient context from which to draw any conclusions from the OP post. More context and more data needed (for me).