Coaching staffs may be pretty comparable. QBs appear to be comparable. That leaves 21 other guys on both sides of the ball, where Alabama is pretty much better, except for the Tigers freshman cornerback and maybe the safety.
Alabama's offense is also flat-out simpler, and that's a good thing. Because of the speed and athleticism of their WRs and the Tigers' penchant for not tackling this season, they turn easily executable plays into big gains and points. Tua doesn't have to have a great day, he just has to keep reading the defense well and hit the easy stuff. We could't stop it last year and this defense is not as good as last year.
On the other hand, Burrow is asked to do quite a lot in this offense. He needs to be on fire and his O-line too to do what they do. LSU's OL has not fared well against Alabama for a few years now. Burrow has had a lot of great days, but a "good" day won't keep pace with them. Auburn made him have a "good" day and the team scored just 23 points. Auburn and Alabama have comparable defenses in SP+ and FEI, 23 points won't get it done. There's more moving parts to what LSU does and it's more likely to bog down. Alabama runs fairly simple stuff with nuclear athletes, and seems much less likely to bog down.
This does seem like LSU's best chance in a few years, and as I say, I think they do have a puncher's chance. With some breaks, a near flawless game and Alabama crapping the bed, it can happen. I wouldn't call it likely.