From what I'm seeing, his accuracy is exceptional, and sentiment around the league is that he doesn't miss plays when they are there to be made (compared to other people) and you know they love a QB that keeps the offense on schedule. And this is despite his offensive line being what it is, though part of that is on him.
So knowing what he can do ... a lot of Burrow's appeal -- especially when a lot of QBs have their greatness judged on intangible shyt like being cool under pressure, great in clutch situations, etc. -- lies in the what-if realm. The equity he's gained has absolutely begun running dry, but the what-ifs for him are tantalizing.
"What if his defense was just average?" (The one sustained stretch of decent play by them we can remember resulted in the Bengals getting to the Super Bowl, but losing it because Aaron Donald got a one-on-one block on a 4th down play where Chase was open down the field)
"What if he stays healthy?" (Last time he did, he put up MVP numbers, but his defense was historically bad, so they didn't win enough games for him to get the award. He finished 4th in the voting).
"What if he played behind a good OL?" (He wouldn't get hurt as much, meaning his numbers would be even better, meaning he probably has a MVP award by now and perhaps more on-field success)
The Bengals front office is an broke, abject failure, and this could have been avoided if they just paid early. That said, far too many teams are where they are because folks aren't willing to take less in order to ensure a good team exists, and part of that is due to folks seeing teams like Philly and Detroit pay all of their guys but manage the cap to where player acquisition is still doable.