You just spent far more time ranting about what Spotlight can index, than it would have taken to open the configuration and turn off the sources you do not want.

Cue "discovery" rant.

Defaults are chosen carefully, but they cannot meet every user's preferences. So, periodically spend a few minutes exploring the enormous software package that is your OS, and be happier for it.

I find this vastly more rewarding than complaining on the Interwebs. YMMV.