When I last read Strang's, my course included a lot of spectral theory that was decidedly not introductory regardless of what the title says. Either way, the point is that most non-specialist practitioners don't need that. How often have you truly run into determinants mod N or stochastic matrices in real life?

It sounds like our linear algebra classes were somewhat different though. No one received an A in mine. I had one of 3-4 B's.