I feel like this is a lesson that unfortunately did not escape Google, even though a lot of these open systems came from Google or ex-Googlers. The overhead of tracing, logs, and metrics needs to be ultra-low. But the (mis)feature whereby a trace span can be sampled post hoc means that you cannot have a nil tracer that does nothing on unsampled traces, because it could become sampled later. And the idea that if a metric exists it must be centrally collected is totally preposterous, makes everything far too expensive when all a developer wants is a metric that costs nothing in the steady state but can be collected when needed.
How would you handle the case where you want to trace 100% of errors? Presumably you don't know a trace is an error until after you've executed the thing and paid the price.
How do you suggest evening genders out? Inviting couples is fine by definition; but I only really know single men. It seems odd for me to randomly invite single women I don't really know.