Moreover, SETI really only detects signals intentionally sent straight at us (beyond a small bubble of a few light years where only a handful of stars exist).

Moreover, SETI really only detects signals intentionally sent straight at us (beyond a small bubble of a few light years where only a handful of stars exist). It's not powerful enough to detect ambient EM radiation around other stars. The only conclusion we can derive from SETI results is that no one is beaming a signal at us intentionally and continuously.