I think to some degree sure, but even as far back in 2017, behind a terrible oline, we saw Dormady play behind it as well, and still not eat near the number of sacks that JG did, so you can't place it all on oline play, especially given that the oline started to improve significantly in the back half of 2018, and JG's issues continued on into 2019, behind a much better offensive line.
PFF's breakdown of his 2018 season, showed that the majority of his interceptions and sacks were coming from his holding the ball too long:
Last season, Guarantano was sacked six times, per PFF, in under 2.5 seconds. That’s about in line with the other four guys, all of whom were sacked four times in the same scenario. Guarantano’s “average time to throw” was 2.35 seconds. Fromm’s was 2.38 seconds, a feat he’s repeated exactly to the second the last two seasons
Since he was a freshman, Guarantano has had bouts where he holds on the ball too long. Of his 22 sacks last season, 16 came on plays where he was in the pocket for longer than 2.5 seconds. Two of his three interceptions came on such throws, too.
The problem with continuing to play him at this point, is that he's hampering the development of the entire QB room with his inability to get off the field. In 2018, he had to play every snap possible, even against cupcakes because he needed every snap to try and improve. That inability to get off the field and give some of the other QBs viable in-game snaps, is contributing to us not having a viable backup QB.
Last season he became a liability and was benched, but because Pruitt made the decision to anoint him starter, and give him the lion's share of first-team snaps, our options were an unprepared true freshman, and an unprepared sophomore with zero playing time under his belt.
With the weapons we have on offense this year in the running game, and an actual SEC-level oline, JG will hold the rest of the offense back if he has not improved, and with out Callaway and Jennings, I don't think his "passing efficiency" will be enough to keep him in a starting role if he starts the season the way he ended 2019.