It might be a lazy argument, but it's also the truth. I won't ever be able to convince you that her music is good, and you me the other way around. Another thing that's true is that global pop stars like Taylor usually don't have a very long shelf life at the top. Taylor, for example, emerged at the same time as the trio Rihanna, Katy Perry and Lady Gaga. Perry and Gaga managed about five at the top before fading and Rihanna a bit longer (I know she hasn't made any music for a while, but she had already started to fade a bit with Anti). The same was true for Britney and now lately Ed Sheeran (who's star has faded quite a bit over the past years), and I'm sure there's a number of other pop artists that this applies to. Then one can ask oneself why Taylor has managed to stay on top for so long now? Clearly there's something people keeps coming back to over and over. And when that happens it's hard to say it hasn't anything to do with quality, because generally people doesn't come back over and over for things that lacks quality. So there's that.