We're Rat-rat-ratties

Recently I have been having a shot at Vermintide 2.

I've never played any of the Vermintide games - I barely knew anything about them beyond the name and the Warhammer connection - but a friend of mine gave me it as a present last Christmas. So I gave it a shot. After all, with a name like Vermintide, it would be a given that you would end up fighting a horde of Skaven right?

So we have a cooperative game where four people choose a character from a selection of five and go kill Skaven. And, as befitting the setting, they will attack en masse will bring along both Beastmen and Chaos Warriors along for the ride.
This may not be the first co-op game I've played with some buds but this is of particular note as there is a horde, and I mean a horde, of baddies coming in to be carved up - and in a variety of ways at that. As this is largely unfamiliar territory, I feel compelled to ask: are all co-op games like this?

At time of writing, I am currently seeing some success with the fire mage. I am also observing how closely the game is tied to the Warhammer universe (although I do have issues with the voice of the witch hunter).
But as this a co-op game, the game is dominated by the one guy who has played it a lot and is several levels ahead of the rest of us....