I think by Old School they meant 1980's Nation...Hence why Austin Rock, and the others you mentioned aren't actually old school legends.
Well they had the old RAW set up like it was a mix of 80's and 90's. Plugging RAW is war too.
First off, The Rock and Stone Cold are not legends. They are indeed some of the biggest names in the industry, but I dont know if enough time has passed for them to be considered legends.
Second, yeah, that makes sense, waste a Rock appearance just because the crowd would have gone crazy. You know, we could have gotten a ratings bump by saying The Rock would be there, but nah, let's just get a pop. Hey, we have saved the first sighting of HHH since Extreme Rules so that he can come back and fight Sheamus in a money making program and people crave the moment they get to see him back, but nah, let's just put him in a DX segment with HBK, who people haven't seen him since his classic at Wrestlemania.
I thought you said you knew the difference between legends and star power. Roddy Piper is a legend. Stone Cold, the Rock, they have more star power, you can still get money out of them, but they are not yet legends. Is a matter of aging.
And if you want to get technical, WWE didn't say Raw was going to be a night of legends. They say they were going old school.
Time needs to pass to be considered a legend? It's about what you've done to be considered a legend not how old you're. Yes, time does help create a legend but more than half of the guys shown aren't legends. Just because Jimmy Snuka is old and jumped off a cage doesn't make him a legend. Legends are guys that mean something and a few of them actually mean something. Then if you're talking about how time needs to pass, it's been a decade since the attitude era.
Those two guys are two of the top 5 biggest superstars of all time. There would be no attitude era if it wasn't for them. The Rock vs. Austin rivalry is regarded as one of the best rivalries of all time. The Rock and Austin have done more for the wrestling business then every "legend" who was on the show combined easily.
Again, the guys who were on the show expect for DiBiase and Piper were purposeless other then to show old school guys. So having all but two of the guys was a "wasted" appearance and having a nice surprise for a change something unexpected is a "wasted" appearance? Surprise is nice and actually seeing guys people care about is also nice.
To clarify on HHH making an appearance. I understand he is selling for Sheamus and there is anticipation for his return so I'm not actually saying he should have been there, definitely not a live appearance but I don't think him having a short skit would be so terrible.