Subjective opinion is ok, but subjective. You should rephrase it to "Why does most music I've listened to that was made after ~2000 suck?"
There. That's a concrete statement, not open to interpretations.
Are you willing to listen to music in other languages? Even languages you can't speak? Because if you aren't, then that would be a shame and a waste. Sooo much good music out there in many languages, you would be limiting yourself to the stuff you've stopped liking.