We used to have classic matches yearly and then you list 3 from 20 years ago lol. I'm not even talking about classic matches because it's a completely subjective matter. If you don't feel satisfied after paying $60 for the show, assuming that you do and don't stream, then just imagine how, not even disappointed but utterly outraged, the people who paid $2000 to attend would feel if they didn't get at least 1 big match that delivered. Regardless of my own or your personal opinion, for 90% of WWE fans, matches like HBK/Taker, HHH/Taker and Rock/Cena tick the satisfaction box. I don't see how you can claim this years Mania was approached as being just another PPV. HHH/Taker was one of the best built matches we've seen in a long time and was 4 years, you could even argue 20, in the making. Despite it's flaws, Rock/Cena was promoted to death for one full year as well. You can't get a more hyped or promoted top 2 matches than that and for most people, they delivered big time, especially the former.
HBK/Hart, HBK/Razor, Owen/Hart, Austin/Rock... I can name a few more. But it has been a string of fairly forgettable WMs for a quite some time.
Rock/Cena was PROMOTED for a year. But the build was not there for the full year and inconsistency showed through all the way past when Cena forgot the loss was supposed to be devestating. And really, it wasn't built at all til the last month or so when the Rock showed up consistently.
HHH/Taker... the build was simply "I have to beat the streak!". Granted, it was decently built, but again it was only the LAST MONTH that it built. The rest of the "build" was again, something from the past. I am not saying it wasn't good, but when you really compare the build and match to what came before, it pales in comparison to the classic moments. But I think the issue we are really caught up on is that you consider promotion and hype build... I don't. It's promotion and hype. Build isn't hyping up a match or promoting it to all over... build is creating an interal logic to why the match is happening, what it means, and what would logically be the fallout. Rock/Cena never really had that and HHH/Taker had a month full of that to where you felt there was a REAL reason the match was happening.