OpenTelemetry-go makes it hard to migrate to exponential histograms
github.com/prometheus/client_golang has a nice feature where a histogram can simultaneously be both an exponential (native) histogram and a classic (explicit bucket) one. Then, depending on what formats are accepted by the scraper, either both the native histogram version and the classical one are exposed, or just the classical one (text format). There has been an initiative to expose native histograms in text format, but it hasn’t yet solidified. Unfortunately, in the OpenTelemetry standards, a histogram at any point can only have either explicit buckets or exponential buckets. From https://opentelemetry.io/docs/specs/otel/metrics/data-model/#model-details: ...