Well there's definitely still places where you can flex those muscles! There's nests that you have to go into buildings and clear out, which still requires you be able to dodge and loop through rooms. Getting stuck in a room that doesn't have a window to jump through or a second door is a death sentence unless your gun is way over-leveled for the zone you're in.

There's also a couple other mission types that are "hold out" style that you have to perform in similar ways.

The open world does affect it though, in my opinion for the better. The map has three zones of increasingly difficult enemies (the ones from Cold War Outbreak are back) so you can pick how far you want to go on any given match. The goal isn't to hold out for as long as you can until you die (though you can if you want) but instead the goal is to find and extract items that will allow you to upgrade your gear quicker (all pack-a-punch, rarity upgrades, and perk colas reset on extract) so that you can drop in and gear up fast for a high level set of missions that will earn you higher level equipment and upgrades. Including schematics so you can craft the upgrades eventually and have a little bit more to roll with from the get go.

So basically, perk sodas, P-A-P, and rarity are extractable items that you can stash and stock up (in addition to weapons) and the gameplay loop is either in building your character out for high level missions or acquiring a backstock of critical perks and upgrades so you can drop in and upgrade immediately to go straight into the hot zone. If you survive, you have to extract. Which can be done either at the least dangerous zone but based on the given match's randomness could also be in a higher risk zone as well.

Extracting is just mowing down hordes of zombies while trying to defend the helicopter until it takes off.

It's functionally DMZ+Outbreak, but the itch it scratches is closer to L4D than old school zombies. If you really like the idea of getting to high waves and pretzels with a ray gun it probably won't be enjoyable, but for someone who's always wanted an open world zombies game done right, it's perfect.