If we want to compare year-over-year improvements, the recent example that came first to my mind was the Suns, who had a 50% y-o-y improvement between '19-'20 and '20-'21. That Suns team didn't change a lot, and had only one major change: Rubio --> Chris Paul. They also swapped out Oubre --> Crowder. Other than that, they had the same coach, and 8 of their top-10 guys earning minutes were on the team the previous year (and 7 of those 8 again in the top-10 in minutes). One big change (and keep in mind Rubio was a .116 WS/48 guy, not a chump) and they went up 17 wins.
We have a lot more than one big change. 5 of our top-10 in minutes last year are gone (Haliburton, Hield, Jones, Harkless, DiVincenzo), one is unlikely to play top-10 minutes (Metu) and one is likely to be an entirely different player (Holmes).
If we ask what's the same from last year, the answer is Fox/Barnes/Mitchell (who should improve as a sophomore). The rest is basically new:
Domas (~= Hali, better fit)
Murray (> Harkless)
Huerter (> checked-out Buddy)
Monk (> diVincenzo, probably)
A focused Holmes (> distracted Holmes)
Lyles (> Jones, probably)
Also, we have a new coach, and I think we all agree Brown >>>>>>> Walton/Gentry.
With that amount of change in the guys playing big minutes, of course we have a chance to make a big change in our y-o-y record. There's a lot more change here than the Suns had a couple of years ago. Now, that doesn't mean we WILL improve up to playoffs level, but with that much turnover, there's no reason to say, oh, we're the same team we've always been. Nope, very different team. Different coach. Looks like a different attitude.
We're not looking at a tweak from last year's roster. The team that going to take the court on Wednesday didn't exist last year. It would be foolish to put a low ceiling on their season before they even start playing - especially given what we've seen in preseason.