Think you are confused. The article makes the assertion that Mooney is a 3 on a good team so all that is required to prove the article wrong is to find a good team where he isnt a 3 as the burden of proof is on those making the assertion.
Now lets go thru all the playoff teams and rank Mooney.
1. Bills - He would be a 2 behind Diggs.
2. Pats - He would be No 1.
3. Bengals - 3 behind Chase and Higgins
4. Steelers - Definitely behind Johnson but I would put him ahead of Chase but fine lets put him 3 just for shits and giggles.
5. Titans - 2 behind AJ.
6. Chiefs - 2 behind Hill
7. Raiders - No 1.
8. Cowboys - 2 behind Lamb as Cooper struggled this year. But fine lets put him 3 to make you feel good.
9. Eagles - No 1.
10. Pack - No 2 behind Adams
11. Rams - 2 behind Kuup but will put him 3 behind OBJ even though Mooney had better year.
12. Zona - 2 behind Hopkins
13. SF - 2 behind Deebo
14. Bucs - 3 behind Evans and Godwin.
So the reality is ESPN is obejctively wrong. The evidence is he would be a 1 or 2 on 9 of 14 playoff teams from last year if you are being conservative or 12 teams if you put him ahead of Chase, Cooper and OBJ.
Math is math and you and ESPN's math is simply wrong.