What about InfluxDB? Speaking of standards, it’s worth noting that this system was created early on, when microservices were emerging as a concept. Another reason this “de facto standard” emerged is that there were almost no alternatives. This is what we need to understand about standards and who promotes them. But technology doesn’t stand still, and I wouldn’t call Prometheus the standard right now, because OpenTelemetry is already starting to be referred to as the standard in the field of observability. Some people like it, some don’t, but Zabbix and Nagios are still going strong; for some, they remain the standard for monitoring for a variety of personal reasons.