Heretic of The Seventh Circle
A weapon attack is an attack.Please show me where in the "attack" action it refers to a "weapon attack?"
By your reading grappling and shoving are also ok because they replace the "attack." But it's not an "attack" it's a "weapon attack."
If the designers had intended otherwise they could have left the word "weapon" out and it would be 100% perfectly clear. But they didn't, it's in there and so it's not an "attack" it's a "weapon attack" - whether it's intentional or it's just sloppy, It's different.