The Article names different acts other than pop stars. The OP creator chose to leave certain Acts out. Taylor was in the Article & girl has dominated over the other girls for years now.
Maybe in the US but not over acts like Gaga and Rihanna on a worldwide scale.
Not so sure about Lady GaGa, she was a phenomenon during 2009/2010 but her flame burnt out really quickly, she was massive but to have already peaked so early isn't good. Beyonce isn't so hot right now but her career progressed and she is pretty much guarenteed to become a legend, Rihanna is peaking to new heights every day and is the hottest female artist in the game right now and has been consistent with that since GGGB minus the rocky start to Rated R
I would have to go on another thread to state why I and many others would leave her out. You guys would catch feeling if i stated it here.
But Like I said the Biggest Pop stars today are Rihanna, (also in the article)Taylor & Adele. Look at the charts, sales. Etc.
We're talking GLOBAL. Gaga is a lot more global than Taylor, and you know it. You mentioned single sales. Taylor's biggest hits haven't even outsold Gaga's biggest hits. You mentioned touring. The Monster Ball has grossed more than all of Taylor's tours. In fact, the only pop girl grossing more is Madonna. You mentioned album sales. Gaga is outselling 99.9% of the industry, so either way you look at it, she belongs in the Trinity.