The way I'm seeing it, at least on TV, is that Guyton either doesn't know his technique that well or isn't confident in it. He looks awkward and choppy, because he's thinking while he's playing.
I play golf, and I see people do it with their swings all the time. There's 100 thoughts going through their head every time they take a shot. "Keep your head down", "keep your weight between your feet", "hands ahead of the club"... they try to track everything at once, and then they just awkwardly chunk their 7 iron into the ground.
On every rep he takes, Guyton looks like he's thinking "flat back", "wide base", "left foot back first", stuff like that. And then when he thinks about hand placement on the defender's pads, then Myles Garrett bull rushes him in the chest and all those plans go to hell.
Guyton started 13 college games, and practiced offensive line at D-1 for 2 seasons. He's now a 3rd year NFL vet, but by game reps, he has about as as much experience as a college senior. So iffy technique isn't surprising, but he's got work to do to make it up.
Can he make it up? Does he really want to do the work to make it up? Was he just gonna suck anyway? I don't know the answer. We expected that he was going to be raw, but so far, he's been a lot rawer than we hoped for.