Sure in hindsight he should've stepped up. But initially with TAA falling asleep and Gomez stepping out to poorly close down Elanga, VVD was left by himself to cover the space for 2 defenders.
If a proper DM (Fabinho) was there instead of Milner he would've been positioned better in the box to begin with and then I also doubt Fabinho would've been juked out like that by Sancho. But all we see now is VVD doing an impression of Alisson with his arms behind his back
Again he should've stepped up to close down Sancho but there are bigger culprits for that goal.