Most likely they will let AppD die.

Why? I haven't used AppD in ~7 years, but I remember it being one of the most pleasurable APMs (but also ridiculously expensive)

It seems to me the marriage between APM and logging would be a home run.

Splunk bought SignalFX a while ago and they are trying to lean in hard on the observability craze and piggybacking on OpenTelemetry. I wasn't involve heavily in this migrate to Splunk Observability Cloud project about a year ago but it was a shit show and half-baked and ultimately they dumped it in favor of DataDog IIUC (I had since changed jobs but kept in touch with ex-colleagues).

* https://www.splunk.com/en_us/about-splunk/acquisitions/signa...

* https://opentelemetry.io/

* https://www.splunk.com/en_us/blog/conf-splunklive/introducin...