I think he's saying he thinks that each AoS Warscroll sets the power of a unit at the same for WFB, and that you can build an 8th ed list using points and it will be equal.
I don't agree, some units in AoS are way better than they were before. The Helstorm Rocket battery, and Celestial Hurricanum for example. The Hurricanum would be worth at least 500 points if it was as good in WFB.
And the combat mechanics in AoS may have a to hit and to wound, but neither are modified by the enemy you are attacking, unless they have special rules, and that includes shooting, where in WFB, they are modified by the enemy.
The combat phase most fundamentally changes the game, you can in effect have Lizardmen with Always Strikes First and Elves with Always Strikes Last, depending on the order you activate units.
The games are very different, in general, I can see why he might think they are more alike goblins are still worse than human, and humans are worse than ogres, but it's not as clear cut any more, a unit is equally effective against anything with the same save value, it's just a matter of how many wounds the target has, that determines how many models are killed