I think the major fault in that X redesign is how the helmet covers the entire face. It makes the character unrecognizable.
I've seen more realistic designs of Link, Samus and Pit that keep the iconic traits about them. The art style is one thing, another is the characterization of the characters, which is what is at fault with the Bomberman and that X redesign. You can change the former without changing the latter.
I don't know why people are complaining about Link, Samus, and Pit's designs. They have art styles that associate with them. Link is associated with fantasy which can be in a old-school medieval-based ones like his early games and A Link Between Worlds, a more fairy-tale, "kid-friendly" like Wind Waker, A Phantom Hourglass, Spirit Tracks, Minish Cap, and Four Swords Adventures, or the more "modern", updated feel from Twilight Princess, Skyward Sword, and Zelda Wii U. Samus was sci-fi from the beginning. "Realistic" or not, she's going to look like that unless they wanted to take a chibi, cutesy route for some reason. When I think of sci-fi, I think of stuff like Star Wars, Star Trek, The Hitchhiker's Guide to the Galaxy, Back to the Future, Mass Effect, Mega Man, Halo, Vanquish, Dead Space, and Metroid. It's just the theme of sci-fi. Sure, you can make it more cartoony like Mega Man or Star Fox, but what else are you going to do? Sci-fi is usually associated with fantastical, awesome tech like super suits, space suits, laser beams, space travel, HUD displays, holograms, and such. Pit went from pixel art to a fun and cartoony design. There's nothing realistic about him aside from say, his feather, hair, and other textures.