The create-a-character story in SF6 has been a unanimous success? I've only heard people saying it's a shallow grind fest that does the bare minimum of teaching you the controls, with a preference for modern, that really only ends up being a "jam as many goofy supers into the toon as you can" mode.
And let's not pretend like it takes much to be better than NR's story modes in the first place. Konquest was fuckin shit, and only worth doing for unlockables. Then they fucked it up more in Armageddon. We also had Shaolin Monks which was a glorified beatemup.
So considering that competition, and the failure that was SFVs story mode, calling the 6 one a success is like saying your shit stinks less than the other guys.
Plus I'd argue NR is constantly caught off guard by their own shadow. They haven't gone one fucking game without changing everything up. From the character designs to the gameplay. The only constant since the 9 reboot has been x-rays, and that's largely considered a shitty addition because it's like Ultras in SF4. Either you do it raw and chunk the enemy, or you combo it and the scaling fucks you while you waste your meter as well as just padding out game time when used.