Good article, thanks for sharing. I've been working on one part of this problem space for quite a while too. I want ability to directly drill down into latency reasons and underlying application component threads' wall-clock time, instead of having to correlate various systemwide utilization metrics and try to manually connect the dots.

I'm using eBPF-based dimensional data analysis, starting from bottom up (every system is a bunch of threads, including distributed systems) and move up from there. This doesn't replace existing distributed tracing approaches for end to end request view, but gives you deep observability all the way down to each service's underlying threads' wall-clock time (where blocked, sleeping and why, etc).

At this year's P99CONF I will launch the first GA release of my (open source) 0x.tools xcapture eBPF collectors, with a reference implementation of a TUI tool, showing dimensional performance modeling on these new thread sampling signals (xtop).

A couple of 1-minute asciicasts of xtop are here: https://tanelpoder.com/posts/xcapture-xtop-beta/