My turn away from standards based grading began when I realized it still put students in the same old boxes, students still couldn't articulate what they were doing and learning, and nothing else about the structure of school changed in response.

As @alfiekohn says, lipstick on a pig. A far more powerful combination has been ungraded UDL & project based learning: Decentering grades & grading, hyping intrinsic motivation, & providing as many on ramps & opportunities as possible for access & expression. If you build it...

SBG just became using generally poor rubrics as blinders for anything that didn't fit within the standard, and naturally it led to standardization. Standardization of gradebooks, of content, and of instruction.

And at the end of the day it still reduces and averages student performance down to a single, supposedly objective, letter grade. Defeating the entire point.