The real explanation for the whole "Consistency" debate has a few reasons
>Tournaments are huge now and so the average high placing pro has to play far more bracket matches than they used to
>The average player is much better than they used to be, we have proper ranked, availability of tech, and really good netcode to thank for that
>SF6 is a stressful, fast paced and high damage game and mistakes are more costly, but they're still mistakes
Given the above, a pro player going far in bracket is more likely to be mentally taxed and more likely to slip up, and the average player being better means they have a higher chance of causing an upset because they likely can take advantage of someone playing below their usual standard. So it's not really that surprising that pros occasionally drop games to players they wouldn't lose to 9/10 times in a vacuum.
Does that make sense or am I smoking crack