Golding’s 2017 defense ranked seventh in the FBS, allowing just 287.8 yards per game.
I don't think anyone is disputing that Golding was a bit of a commodity when Saban hired him.
At the time, he might very well have been considered a top ten DC. Then again, Anthony Grant was also a hot commodity when Alabama basketball hired him, and we know how that turned out.
The reason might very well be the same one. Success at a lower level of competition does not guarantee success at a higher level. Anthony Grant did extremely well at VCU, then struggled at Alabama.
In this case, UTSA played the 140th ranked schedule in 2017! So did he do well at that lower level, but that did not transition to Alabama. I have noted a few times that the highest ranked defense he's coached was at UTSA. That's actually really problematic considering how much more he's had to work with at Alabama.
He just might not be cut out for the Power 5, Alabama is his first Power 5 job, he didn't even attend a Power 5 school, he had 0 experience at this level and it shows. Obviously the coordinators he was matched up with were at a different level and in-game adjustments seem to be a weakness of his.