I don't see why a stage banned in a past smash game should be legalized. I mean, it was banned for very good reasons, and the smartest and biggest TO's, players, and so on agree with it for good reasons.
You need to remember something. Top players are looking out for their own interests, not what is best for the game. Guess what, many top players have advocated for stages to be banned (and other things now like custom moves) simply so they have less to learn and have an easier chance to win. This is not uncommon, and without breaking confidence of some people I have talked to, players DO do this on purpose.
Plus, stages were banned in the past for different reasons then they are now. If a stage has significantly changed, or maybe some things have been removed (no chaingrabs), or physics changes have made the stages work better they need to be evaluated.
Of the "Familiar Stages" in Smash Wii U, the following are neutral stages in past Smash games at APEX, which is seen as the Super Bowl from Smash (even if it's missing the 2nd most played Smash game):
-Final Destination (all games)
-Battlefield (all games)
-Congo Jungle 64 (Smash 64)
-Smasvhille (Brawl)
-Lylat Cruise (Brawl
The following are counter-pick stages in past Smash games at APEX:
-Battleship Halberd (Brawl)
-Castle Siege (Brawl)
Aside from stages that suffered from being "too big" (not stage hazards) that could work in teams play and just teams play (Delfino Plaza is basically the only "Familiar Stage" that fits this billing), there's no reason to even discuss other past stages, and it is why top competitive players don't do such things.
Are you kidding? Maybe we're discussing other stages because they 100% work in a tournament setting and have massive player support. I can say every stage we're currently running for Hypest Tournaments have causes ZERO issues thus far. Delfino especially work just fine in singles, along with it's "brothers" Skyloft and Wuhu (though some people are on the fence about the latter). Where is Duck Hunt on this list, a stage ran in loads of tournaments that have been highly successful? Where is Pokemon stadium 2 which has been toned down considerably from Brawl and is not only being successfully legal in tournaments but is a counterpick on Anther's Ladder, the largest online matchmaking place for Smash 4 and has yet to cause a single issues depite hundreds of matches being played on it? (Speaking of stages that have changed, Kongo Jungle has had adjustments to size and how high the rotating platforms go to prevent camping issues even).
Especially with stages literally changing in front of us, you can't say "It was banned before, ban it again" without be highly irresponsible as a tournament organizer and actually learning about these stages.
There's clear design issues on all the other stages that prevent it from being a fair competitive stage or to have matches finished on time (so we can get home from tournaments on time and not almost 8 hours late like the latest KTAR; TO's care about time and efficiency above all else) that have been exploited, discussed, and covered.
Melee as a national game didn't grow as fast as it could because its' stage list was too big and thus the game had camping issues for too long, mostly caused by having too many legal stage. A big reason Brawl disappeared from all majors outside of APEX is because majors wouldn't carry it because sets went too long (which has happened at APEX a lot, lol), which was in part due to a huge stage list.
Let's not let history repeat itself, especially when all the top smash minds (specifically THE BEST TO's) are telling us to be conservative with the stage list at majors. It's because they run tournaments, they know what's beset for the scene, and they know having certain stages legal is a problem for time at majors.
(this post was all about majors BTW. I don't really care about other tournaments' rulesets unless I'm attending them or watching them, lol)
I can say my stagelist causes NO issue with tournaments running on time. You want to know what makes tournaments go long? Bad TOs. Yes, Brawl was a long game at times, but Smash 4 is no where near as slow. These top TOs you mention are the same kinds of folks who ban stages just because friends who are top players say they don't like it there, or ban a stage because a glitch on a video that can't even be reproduced showed up, or who are running tournaments with terrible inefficiency. Going to call out KTAR pretty hard here: HE RAN HIS TOURNAMENT BADLY. He didn't have enough setups, didn't even have a backup plan for if more people showed up then expected, and couldn't adapt on the fly to make it work, AND matches that should have been on stream were lost forever. I'm a TO for reddit and we have backup plans EVERY week for if player attendance is past what is expected, you mean to tell me a highly respect TO hosting an Apex qualifier didn't think about that? Plus when was the last time ANYONE said Apex was well organized and ran correctly? I have heard nothing but complaints about organization at Apex since, well, forever.
Some TOs also need to grow a pair and start actually DQing players who are making things run slow too, even if they are top players. I saw a stream where they waiting 45 minutes for a player just because the stream wanted to see him. He had left the venue, told no one where he was going, and it was in the middle of the event. He never was DQd. I don't care if M2K enters my tournaments, if he pulled that crap he'd be in loser's bracket or more likely out the door. Top TOs need to stop sticking up for top players or friends who act like they run every event they go to and make special accommodations for them. This happens WAY too much and it also makes new players feel like crap when they lose a match or get DQd but if the privileged player does something they're off the hook. You wanna kill off new players joining our scene, that's a great way to start.
All of that, and you will have events running on time. Don't make up garbage about banning stages to make events go faster, it's utterly ridiculous.
I run tournaments too, you want to know what is best for the scene? Not banning things for no good reason. We have loads of new blood and talent coming in for Smash 4 (I've wanted to somehow pay out of pocket to sponsor some players at my events to go to Apex, THAT good of talent) and a lot of these folks are going to be driven away if we start banning perfectly good things for no reason. They're going to think we're stupid, and they will be 100% correct in calling us morons if we do.
TLDR: Never ban until proven banworthy. Don't trust top players who have an interest in continuing to win money vs making the game the best it should be, TOs need to not john and actually run their events properly, all stages deserve proper testing, enough with knee jerk reactions, and people need to not be scrubs and just ban what they don't like or get away from my competitive scene.