They're pink because they eat shrimp. Dying the food is a cheap hack, but not really surprising I guess.
So other than "not the same", how would you compare the taste of salmon vs. trout? I remember the stuff I ate as a kid being OK, but have since decided/realized that mom was not the world's best cook. It's entirely possible I'd really like it if done well.
I haven't particularly liked the salmon I've had as an adult. But the two or three times I've tried it were either at a buffet -- an environment not noted for great seafood -- or grilled by someone who might not have had that much experience with it.