So then Nickelback could be subjectively BETTER than Led Zeppelin because there are some people who would rather listen to Nickelback than Zeppelin. But most discerning music fans would find that statement pretty absurd. Saying Nickelback is better than Zep is like saying something illogical. It's like saying that a piss tastes better than orange juice. Come on, then we can say that the answer on a question "What tastes better: piss or orange juice" is not objective, but subjective.
I knew someone is going to throw Nickelback as an example since they are everyone's favorite rock band punching bags around the internet (Creed, as well. Not here though, but elsewhere).
Here's the thing. I am not a classic rock listener, I usually change stations if I hear a classic rock tune if there a modern rock track that I want to listen to elsewhere. Some people would actually like to listen to Nickelback over Led Zeppelin for their own unique reasons. If I had a choice listening to a Pink Floyd, Black Sabbath, AC/DC, etc. track or a Nickelback track, oddly enough, I probably would choose the Nickelback track. Heck, I've been listening to Nickelback more than the majority of the heralded classic rock bands in recent times and not regret that thought process.
Would I say Nickelback is the better band than those bands? I can't honestly say that, but I also can't say that those older bands are better than Nickelback, because that's not how I want to view music. I view what music I listen to more on my overall enjoyment which is based on a variety of things that only I can define. People can listen to what music they want to based on what they want for their own personal reasoning. How else would a guy like Ed Sheeran (who I like) draw stadium crowds over bands we feel is sorely overlooked? It's because people would prefer listening to a guy like Ed Sheeran and want to see his show above all else for their own unique reasons. It can't be something that's easily defined.
The same goes for wrestling. Who is the best wrestler of all time? What can we based that off of? It could be a lot of reasons. Their drawing power and attendance to crowds and PPV buys, how they wrestle a match, how they talk in interviews, engage their crowds, etc. People would say Hulk Hogan is the best wrestler of all time. Some would say Stone Cold Steve Austin. Some would say Ric Flair, The Rock, Bret Hart, etc. It's something that cannot be easily be looked at and go, "That is the definitive answer and anything else is a crap answer." The same goes for music as well.
Musicians and wrestlers are not like sports athlete in that sense where we look at an athlete stats in a career and go "this is the greatest basketball player, football player, hockey player, etc. in the world." Even then, some people in modern times would argue whether or not a guy like Michael Jordan or Wayne Gretzky would complete, like the greatest of all time players they are deemed, in today's sports environment in comparison to a guy like Lebron James or Sidney Crosby.