The ongoing feud between the two stars has a modern feel. They've referred to each other by their real names, and The Phenomenal One brought up The Undertaker's marriage to Michelle McCool.
The Deadman also noted his wife used a variation of the Styles Clash as her finishing move.
This isn't fresh territory.
John Cena broke kayfabe in the buildup to WrestleMania 34 in 2018 when he said The Undertaker was still physically able to wrestle; otherwise he "wouldn't be posting workout videos on [his] wife's Instagram."
The tone and substance of The Deadman's segment Monday didn't differ much from any other promo directed toward somebody who built their reputation in another wrestling promotion. Triple H and Stephanie McMahon hit those notes prior to The Game's WrestleMania 31 battle with Sting.
If this was scheduled to be a traditional singles match, The Undertaker vs. Styles would probably be enjoyable but ultimately forgettable. Few people fondly remember The Phenom's recent encounters with Cena, Goldberg, Triple H (the 2018 Super Show-Down bout), Rusev or Bray Wyatt.
By taking this feud out of the ring for a "boneyard" match, WWE opened the door for something that could be a lot of fun.
Styles confirmed he and The Undertaker are crossing paths in a cemetery—or at the very least a cemetery-like atmosphere if WWE didn't get the approval to film in an actual graveyard. The gravestone with Styles' name on it implies this could be some sort of Buried Alive match too.
Treating professional wrestling as an actual sporting competition is good and should be the way WWE approaches the product the majority of the time.
Sometimes, though, it's good to remember The Undertaker is an undead mortician who occasionally channels his power to summon lightning.
His WWF Championship match against Yokozuna at the 1994 Royal Rumble wasn't very good, but fans from that generation still recall watching him rising to the rafters of Providence Civic Center.
Especially since he's so limited in what he can do in the squared circle, WWE should lean harder into the supernatural aspects of The Undertaker's gimmick. Let him operate in his own universe.
The rapid explosion of "The Fiend" Bray Wyatt demonstrates that there's an audience for the occasional departure from the traditional fare on WWE programming.
Looking back at a low point for Wyatt, his House of Horrors match against Randy Orton at Payback 2017 didn't fail because it wasn't wrestling; it failed because WWE didn't lean hard enough into the concept.
The production team hopefully learned from that mistake when it laid out Wyatt's Firefly Fun House match with Cena at WrestleMania, as well as putting together the "boneyard" concept for The Undertaker and Styles.
The Undertaker's legacy is assured. He doesn't need to add another classic match to his resume. If WWE is willing to think outside the box, though, it can make him front and center in a WrestleMania moment the WWE Universe recollects for years to come.