Sh o v in g a C r e a t u r e
Using the Attack action, you can make a special melee
attack to shove a creature, either to knock it prone or
push it away from you. If you’re able to make multiple
attacks with the Attack action, this attack replaces
one of them.
There is nothing here about limiting amounts of shove per turn. The sentence is there to make a distinction that if you have multiattack shoving will replace one of the attacks not all of them. Considering the context that is what this sentence refers to.
If it’s purpose was to highlight that you can make only one push per turn regardless of multiattack it would be worded differently.
