How do you not be the best player in the game if you have that level tech skill? Not even Ken could out tech-skill what's in that video.
Last I checked tech-skill was 99% of how you win.
Tech-skill is vital to expanding what options you have and how much you can profit from punishing a mistake, but what's even more important (especially in high levels of play) is how smart you play. In an interview, Lovage stated that Mango has one of the worst tech skill compared to top players such as Armada, Dr. PP, and Mew2King, but the reason why he's so successful is because he plays so intelligently. High level of play revolves around positioning your character so that you can limit your opponent's options while remaining as safe as possible (spacing); this is especially true when both players are in the neutral position trying to get the first hit. Having all the tech skill in the world doesn't help when you are constantly put in bad positions such that you can't get any momentum to attack your opponent and they can read which option you pick.
Cactuar is a textbook example of a player who's notorious for displaying relatively (note: relatively) little tech skill compared to other Fox players but is extremely good at positioning himself so he can score hits without being counter-attacked.
Also, Ken wasn't technical at all compared to today's standards; Ken's strengths were his god-like precision in his dash-dancing and ability to get good reads. I remember an old video where he played Mango's Puff at Evo and baited Mango into approaching by
FSmashing just out of a punishable range, then shielding and counter-attacking. Granted, that Mango is clearly not the Mango of today, but it just goes to show how far you can get by good positioning and reads.