As we have seen, without him Muhammad Rizwan and Saim Ayub cannot even hit a boundary and the first boundary hit in the 5.5 overs (in the match against Canada) and that was hit by Muhammad Rizwan but I am sure if Saim Ayub playing with Babar Azam then for sure, he also hit the boundaries at the start and didn’t waste the powerplay option where you can easily hit boundaries.
And regarding Babar Azam so Babar Azam don't have consistency he should have consistency to lead the team. Mostly we have seen if the leader step down so all the team step down so I think Babar Azam also need some practice to perform well.
By the way I agree with @Publictalk792 PCB should enter the new talents in team.