The alternative is Prometheus (which is freaking great) and Jaegar (which is freaking great), each alone. This is better, because Otel is trying to put two distinct things (monitoring and metrics, distributed tracing) into one package, because they know how to use neither.

Neither Prometheus metrics nor Jaeger traces are magic bullets. Neither of them are complicated, either, and in fact the fact that they're not complicated is their greatest strength. You can and should understand every facet of what they entail. You should build the (very small) shims that they need for your company's framework every time. It's not hard. It's not hard because it's not complicated. The fact that it's not complicated seems to break people's brains. They are accurate because they're simple and they're easy to work with because they're simple, and OTel is neither.

I’ve built custom Prometheus metrics very easily and had node exporter pick up the .prom files. Python and bash scripts reading and translating.

Node exporter runs on my Prometheus server next to Blackbox Exporter. Blackbox Exporter handles TLS expiry metrics.

OTEL metrics are a bit awkward, but they work just fine with Prometheus.

Jaeger uses the OTLP protocol nowadays. So it _is_ OTEL.