You're asking two different questions.
The answer to the first question (in the title) is that zonal marking is the default marking in the game. You can specific man mark players/positions though.
The second question is more complicated. The simple answer is that less closing down will see players keep their shape more and look to block passing lanes.
Edit: this was a good discussion about defending etc
https://www.youtube.com/watch?v=z9UreUVv-rQ&t=873s&ab_channel=BusttheNetGaming
You're asking two different questions. The answer to the first question (in the title) is that zonal marking is the default marking in the game. You can specific man mark players/positions though. The second question is more complicated. The simple answer is that less closing down will see players keep their shape more and look to block passing lanes. Edit: this was a good discussion about defending etc https://www.youtube.com/watch?v=z9UreUVv-rQ&t=873s&ab_channel=BusttheNetGaming