The thing that makes me sad about the discussion of ʻOumuamua isn't anything objection to SETI; it's the way it pulls all the attention away from the core of an incredibly amazing discovery and massive work by the discoverers and planetary scientists.

The idea that detectable interstellar comets/asteroids are frequently passing through our solar system is one of the greatest discoveries of the last decade, at least as amazing as the idea that we can detect gravitational waves from merging black holes, and even more unexpected!

It opens up an entirely new window for characterizing planet and star formation and exoplanetary systems! (If you think a 10e12 eV neutrino is multi-messenger astronomy, wait until you see 2e43 eV asteroid...)

@VRubinObs will discover lots of these, and we'll get spectra for many of them from JWST and other facilities. Someday in your lifetime we may get a sample. Interstellar sample return this century! That's incredible. We should all be spectacularly excited about it!