Imo this is more due to not having a character like Zangief, rather than something that applies SF6 as a whole. Because a MU like that isn't reflective of 99% of the MUs in SF6. It's the oddball out of the entire cast.You mention SF6, but that is just, a bad example. Characters like Guile, JP, and Sim have MUs where they absolutely brutalize characters by zoning them out to victory. MK1 has nothing like Sim vs Zangief or Guile vs Lily, etc. But in reverse, you also have offensive God's like Ken with MUs where characters are equally brutalized.
The zoning in SF6 is overwhelmingly not like that of anime games. It's just a very different design philosophy. And in SF6, you'd be hard-pressed to find a lot of matches between the top players where someone is defeated with just zoning. The current best JPs in the world have to play up-close just as much as fullscreen.
This is the best JP in the world facing off against a big-body character. If we ask how much of this match is actually fullscreen zoning or looks like Injustice, it's very little. And that's by design.
If Kakeru depended on just sitting back and zoning the top players out, he'd never make a top 8, because the game's mechanics just don't allow you to play that way most of the time at that level.
If you want another example, here's a match with a bit more zoning. It starts off more fullscreen, but it takes Mago all of one dash or one jump to get in, and then the rest of the set is played point blank or at footsie range. This is SF6 in a nutshell.
In fact, I've seen a lot of top player MK1 sets this week with a ton more zoning then the majority of Kakeru's JP sets. Including this one. Compare how many rounds here are won by a projectile: