Why Eminem is obsolete in modern battle rap

When Eminem started, he was on fire to make it in the rap game leading him to freestyle battle to put his name out there which worked very well. Since then, he's been blazing and essentially invincible when it came to diss tracks after he became famous. Once he made it to the top, he didn't see the need to battle rap anymore. 

Eminem is a talented artist in lyrics and has made many solid records but the reason why i think he's not competent is because the battle rap scene has evolved over the years. Back then, freestyle battling was a thing along with DJ's. If you could freestyle tons of impressive disses then you were respected and declared the winner. Now, battle rappers are judged by different standards. Battle rappers prewrite their bars, use many literary devices, entertain the audience, and so forth. Rappers no longer battle rap just to get ahead. It's become a lyrical competition in it's own respect. 

I think Eminem understands that since he's from a different generation and that is why he won't battle rap because he doesn't want to disappoint the fans. I believe that he is unbeatable on the track but he shies away from being put on the spotlight in a battle league. Because of differences in generation, we may never see Eminem battle again.