At the previous company I worked it turned out pretty well. We used Grafana (which is OpenSource) for our high volume in-app analytics and servers monitoring. I

At the previous company I worked it turned out pretty well. We used Grafana (which is OpenSource) for our high volume in-app analytics and servers monitoring. It took a bit to implement all the graphs, but we had exactly the graphs we needed. Even if we went for a SaaS, we would still have had to implement those custom graphs in their interface. We have also paid (a lot) for DeltaDNA to have more insights into monetization, but their platform was a lot slower than our self-hosted Grafana and they even forced us to use our own S3 buckets to store the data (set them up and link them) due to GDPR (they said). Not only that, but creating custom graphs in their platform was very tedious and a bad experience overall. I am not saying it makes sense to always go self-hosted, you are right that depending on the application you want to host you might need less or more technical knowledge and maintenance. I would never recommend (for the average individual/company) to self-host email servers, CDNs or Slack chat server alternatives, but I do think for some applications it's worth the time, for example static pages (instead of using a website builder get a theme and host it yourself) or analytics.