The playcalling and "Tush Push" are the only things keeping him from being in the argument for #1 RB overall.
But those are two very big things to be concerned about.
I'd argue talent is also keeping him from #1 overall RB. He's nowhere near the player CMC is, really at anything, even power running. Barkley is a good player, but man, he gets a lot of leeway for his numbers, because the Giants weren't good. Lots of other RBs produced more in situations just as bad. Barkley hasn't been a great tackle breaker or a high-end pass catcher since he tore his ACL. That elite player from 2018-2019 is gone and is never coming back.
Barkley will be good, because he's in a great offense, and should see a big workload, but I don't think he has elite upside at all. I've got him in the RB6 to RB8 range, as a 2/3 turn kind of guy. Which likely means he may as well not even be on my board.
Hurts, probably well, hurts as well. Both from a TD aspect, and a reception aspect. I think 40 catches is a fair over/under in this offense. Maybe 8-10 TDs. I'd consider it a minor upset if he topped 300 touches. I'm not confident he's the best RB (NFL or fantasy) that changed teams this offseason.
I thought Saquon had a really good year last year.
962 rushing yards in 14 games--on pace for 1168 in 17 games.
10 Total touchdowns in 14 games.
41 receptions--on pace for ~50 receptions in a full 17 games.
He finished as RB12 overall in 0.5 PPR.
The Giants lost their starting Quarterback.
They had no quality playmakers at the receiver position.
They had one of the worst offensive lines in football. PFF had them at 29 going into last year. I can't find this year's, but FBG has them at 27.
Guys that finished above Saquon:
1. CMC
2. Mostert
3. ETN
4. Breece Hall
5. Mixon
6. Kyren
7. White
8. Henry
9. Robinson
10. Gibbs
11. Cook
Of the above--who had a situation just as bad?
Breece didn't have his starting QB, but he had a competent WR in Garrett Wilson that the defense at least had to consider.
Mixon lost his starting QB, but had Chase and Higgins. Higgins missed some time but played 12 games.
Henry wound up with Levis at QB--but again, at least had Hopkins.
I just really don't look at the list and think "A lot of RB's had equally bad situations and did even better." I think Saquons probably was the worst. I don't think Saquon winds up as RB1 overall. I have him around 7 or 8 in my redraft rankings. But I certainly think the #1 overall RB upside exists in this much better situation. I certainly don't think we're giving him too much credit for the Giants bad situation.