Likely because there’s only a small minority who know how to read the etl traces properly.

Please note I am not one of these people and what I’m going to say is an assumption.

When your FXServer spikes you have a long tick in the V8 runtime (node) so you might try looking there.

This would also make sense as to why it doesn’t show in the profiler as v8 doesn’t get profiled iirc