This is what changed:
1) You grew up
2) Your experience level of the product increased
3) Your passion for product takes you from casual to wanting to know every little thing
4) With every new match, your standards are becoming much higher
5) WWE's apparent "ZERO CARE" for the product gave everyone a sense of needing to fix the product, yet 3 million chefs in the kitchen, makes it even worst.
(Read bold for straight to point)
Setup:
If your just watching each week, and not keeping up on anything backstage, any drama, etc. and your back when you really didn't understand all the little things like rolling over, build up, jobbers, heaters, managers etc. You see the product much different than someone who has their thumb up WWE's asshole.
Like me, I came back with Brock like many. My thumb was up UFC's pulse, on the bleeding edge of training camps, fights etc. When I started watching WWE full time, I just watched every show, and just used it as down time. I got WWE Network, and watched every PPV that ever happened, I watched every Documentary, I listened to every podcast, etc, this happened when NBA and NFL were in off-season 2014. I think what happens to people is, they stop watching it for entertainment, but take it serious in the wrong way, like hawk eye. See I watch it seriously, like how I watch my NBA team. Its dwindled down to that feeling only for few matches not whole product.
Main:
The 1 thing I notice with these groups of "wrestling fans" on internet, they give WWE shit for the dumbest shit ever. They take everything out of context to make fun of them, or they think they know better so always tell WWE they are stupid, and should have done it this way, or that way, and worst of all, won't enjoy the product unless done 100% to their liking, which is turrible when the product is struggling. Well that mentality is now in basically every smark. Overall, they aren't watching the product to enjoy it, they are watching to analyze it. Just like video game industry, with everyone judging hardware, specs, resolution, etc. it turned every gamer into a god dam critic, instead of thinking how much fun a game can be, they are like "does this game have good enough graphics to even bother". Same with WWE, I think too many people want to tell WWE how to do business. I think its their own dam fault, 2015 and 2016 has been some of the worst television in history.
Extra:
As for me, I came to internet cause I wanted to know why Rusev lost 3 PPV's to Cena. If you look, I joined Forums right after the I Quit match that Cena won. Well I found my answers when I learned of "Super Cena". Since then, my levels of rage come and go, but I lost a lot of love for product around Autumn of 2015. Since then, WWE has given me so much baggage its sometimes hard to enjoy a show.
I think many like me who wanted split, just wanted to drop all the baggage, and give WWE a fresh start. I want to go back to 2012-2013, when I last watched every show, and NXT, and loved every show, start to finish. I mean for god sakes, Roman and HHH main event'd Wrestlemania, when I canceled WWE Network and went a whole month not watching anything, after years of service, I said, I'll give WWE til Wrestlemania to fix everything, and if not, I'm not watching anything for rest of 2016. 51% of wished I had quit the product. This brand split gives me hope I haven't had since Brock returned.