[{quoted}](name=Riot Aesah,realm=NA,application-id=A7LBtoKc,discussion-id=2u9wA1NM,comment-id=00110000,timestamp=2016-10-20T17:46:06.345+0000)
I think you are undervaluing his late game waveclear. Buying time for your team to close up gold gaps in terms of percent is extremely powerful that LB/Corki don't offer.
No kill pressure reminds me of this video https://www.youtube.com/watch?v=z0FUP_5xLXY
Overall as far as I know Ziggs is in a good spot but I can double check!
Go to lolalytics.com and notice that the best Ziggs with 50+ games in Plat+ ELO only manage an average of D4 ELO while the best Viktors, Zeds, LBs, TFs, Yasuos etc. average D1 ELO. His problems are outlined here and here although it's not really the exact subject of the thread.
It's not just a matter of winrate (although I expect this to go down a lot once assassins are popular again). He performs at a mediocre but acceptable level for someone without a lot of experience. It's that he simply FAILS TO CARRY FOR EXPERIENCED PLAYERS in higher ELO since his scalings aren't amazing and his whole kit is dodgeable. Take a look at champion.gg and notice that even Ziggs with 125+ games are just short of 49% winrate. Especially for a champion with a low pickrate, that's pretty pathetic. After 125+ games, Syndra's at 54%+, Ahri's at 54%+, Vel'Koz is at 55%+, Anivia's at 56%, Annie's at 57%, Morg's at 56%, Xerath's at 63%, Brand's at 54%, Akali's at 57%, Kennen's at 52%, Kayle's at 56% etc. I could list probably another half a dozen champions. Considering he's only picked 2% of the time, I'd expect huge winrates for people with 125+ games. Other champions with low pickrates certainly follow this trend. For example, Karthus is at 65% winrate and Zilean is at 60%.
As far as your video, that's 2014 and a lot of things have changed since then for both Ziggs and the game. His auto range was nerfed, his Q hitbox was nerfed, his MS was nerfed, his E was nerfed, his passive was nerfed early and the meta mids now are in a different class. Viktor isn't even considered strong early and Ziggs can't trade with him. He has no shield like Ryze or Viktor, no heal and ridiculous lane/kill pressure like Cass etc. Vel'Koz does pretty much what Ziggs can except for turrets but if you kill your laner, that's not an issue. Vel'Koz has good CC, can get rid of even Dr. Mundo or other hypertanks, has near 1 shot potential with E-R and has a stronger early game. ZIggs doesn't have kill pressure vs competent laners unless they chose to sit in lane after being poked down a lot (which is their fault for being too close to minions when Ziggs Qs). Compare Ziggs to a Cass early... she can pretty much solo you in a few seconds at level 3. Even if Ziggs were to hit everything, he just doesn't do damage that fast. That would be fine if his late game were better but as you can see from the stats, he's not performing well late game either and I don't think it's just from stalling out games. I've played Ziggs late and I felt completely outclassed by Viktor for example while being equally vulnerable. Viktor's extra CC, shields, higher base MS and way higher CC more than compensates for Ziggs' unreliable escape. Also, Viktor can waveclear EVEN BETTER than Ziggs. All he needs is one ability and the wave's gone. Ziggs can do it fairly well too with E and 2 Qs but it's more mana intensive.
I don't want to ramble too much but if you talk to top players, you'll know that those who actually have played Ziggs 25+ games don't consider him good. Froggen actually said "Ziggs sucks." on stream when people were asking him to play the champion. He eventually was forced to play Ziggs through a poll and got fed but couldn't carry. I don't think he played Ziggs after that even though it's a champion whose strengths fit his style. Froggen's used to carrying games from very far behind when he goes Anivia or Viktor. Ziggs is underplayed, particularly in high ELO, for a reason. It's not random when literally every region has played basically 0 Ziggs games this whole season and there's no one in high Masters+ maining him (there are plenty of TF, Viktor, Syndra and Ahri mains/one-tricks). It's not like Ziggs is a new champion and they don't know how his kit works.
EDIT: Corrected site link and added more details.