Take a look at Coroot: https://github.com/coroot/coroot. It supports OpenTelemetry and stores traces in ClickHouse.
Here you can find a demo of the Distributed Tracing UI: https://demo.coroot.com/p/tbuzvelk/traces
Disclaimer: I'm a co-founder
Here you can find a demo of the Distributed Tracing UI: https://demo.coroot.com/p/tbuzvelk/traces
Disclaimer: I'm a co-founder