Imagine how differently the landscape of wrestling would be if Shawn and Bret remained pros and did a three year Mania series. Also assuming Shawn's back injury doesn't happen
12 - Boyhood dream comes true
13 - Bret wins and goes heel
14 - Shawn overcomes Bret and is the man
We may never see Austin reach the heights he did. Bret likely never goes to WCW. Do we get the Taker - HBK mini feud still that leads to the debut of Kane? There's just so many stands of reality that could have been altered
I still say all of that happens, with the exception of Bret going to WCW. Bret really wanted to work with Austin when he returned in late 1996, so we still would have gotten that feud. Austin star was on the rise, and all the people in Vince's ear were telling him Austin is his next star. Had Bret and Shawn remained pros and worked with each other, I see it going like this:
WM12 - Boyhood dream comes true.
WM13 - Bret wins and shows signs of a heel turn.
PPV after WM13 - Bret turns heel and Austin turns face (basically they have their WM13 match that they had, here).
SSL97 - Bret beats Taker in the same way with HBK causing the loss, Bret retains the belt.
IYH PPVs - Shawn and Taker feud, Kane makes his debut.
SSE97 - Bret loses the belt to Shawn in a screwy finish.
RR98 - HBK vs Taker for the belt, Shawn retains. Austin wins the Rumble, last eliminating Bret.
WM14 - Austin beats HBK for the belt.
Aftermath: Austin goes on to feud with Mick, Taker and Kane. Hart Foundation (heels) vs. DX (faces) feud for a while. Bret and Austin eventually meet again in a singles match, Bret puts over Austin. After that, Bret starts to wind down his wrestling career, maybe even teams with Owen for a tag title run.