Lee seemed like a game manger? Not an amazing one, but one. Jefferson less so.
I don’t know that I’d call them efficient (though the usual number I used for that doesn’t go back that far, so maybe). They were a kind of pretty effective with a limited profile, but that was going to his an issue against a really top defense if their defense also wasn’t lockdown. And that day it wasn’t.
He was a game manager when afforded a giant cushion and there was no pressure whatsoever in the pocket. His OL often afforded him that. When they couldn't, he didn't just sink to the levels any decent QB sinks to when they have no protection. That equates to merely failing to help your team. Lee became an active liability. His yips were amongst the worst I've ever seen, throughout his entire career. He got benched in the first Alabama game because of it.
So, you could think of him more as a boom or bust, but in his case, it was more like OK or bust. Against a team like Alabama, he became appreciably worse than most other QBs would've been. A regular QB would fail to produce. Lee cost the team.
Jefferson wasn't any different, other than that his usable skillset when everything was to his advantage was different. He was actually pretty good at running the read-option. Which is where he did his damage against Alabama in the first game, off the bench (what little damage he actually managed to do). Take away the read-option, which Alabama did in the rematch, and he had nothing....not "perfectly fine," not a "game manager," not "okay"......he was trash, with yips nearly as bad as Lee. If there was a moment that was uniquely indicative of their play, something that encapsulated their problems, nothing was more singular than his literal shovel pass to a defensive lineman in the NC. That was nothing more than an ongoing major case of the yips, but it wasn't unique to that game. It was always there, LSU's OL just made sure most teams couldn't make it a factor. He was so scared of getting hit, not knowing what to do, inability to think in the moment under duress....all the above....that he just gave the ball away to someone, anyone.....even if his brain only later realized the guy was wearing the other uniform.
Danny Etling was the QB people want to think Lee/Jefferson were. Etling certainly wasn't great, but he fits the profile of a game manager, "fine" or however you want to describe it, and he probably would've seen the receivers galloping to potential greatness and been able to hit at least 1 or 2 of those.
That said, LSU had other head-scratchers in that game. But I maintain most, if not all, of that would've been mitigated by a QB who didn't piss his pants when a team actually had a shot of hitting him. I know it felt in real time like Alabama absolutely smothered everything about LSU, but I've forced myself to rewatch that game a few times, with the coaches film that used to be available on YT. The truth is that LSU called a number of plays that looked good and had a shot, but Jefferson played one of the worst games I've ever seen.
I hate what that game did to the perception of the two teams, but it is what it is. I'll always believe the first game was more indicative of the two. Not inasmuch as LSU won it, but in that it was close. Most people retroactively think Bama was far superior all along and the NC proved it. I think there's a lot of evidence to suggest that the normal outcome between the two teams would've been close, whoever won it, and the NC was a poor outlier for LSU. But as I said, they had several head-scratchers in that game, and the perception isn't likely to change at this point.