The choice between 4 and 5 is more about what you get to avoid. By choosing level 5 you are opening the possibility to make some really complicated configurations and many more footguns. When you stay at level 4 you're forced into using more "standardised" blocks of code that can easily be looked up online and understood.
Level 4 is also far more declarative by nature, you cannot fully compute stuff so a lot is abstracted away declaratively. This also leads to simpler code since you're less encouraged to get into the weeds of instantiation and rather just declare what you'd like.
Overall it's about forcing simplicity by not allowing the scope of possibilities to explode. Certainly there are cases where you can't represent problems cleanly, but I think that tradeoff is worth it because of lowered complexity.
Another benefit of level 4 is that it's easier for your code can stay the same while changing the underlying system you're configuring. Since there's a driver layer between the level 4 configuration and the system which can (ideally) be swapped out.
Level 4 is also far more declarative by nature, you cannot fully compute stuff so a lot is abstracted away declaratively. This also leads to simpler code since you're less encouraged to get into the weeds of instantiation and rather just declare what you'd like.
Overall it's about forcing simplicity by not allowing the scope of possibilities to explode. Certainly there are cases where you can't represent problems cleanly, but I think that tradeoff is worth it because of lowered complexity.
Another benefit of level 4 is that it's easier for your code can stay the same while changing the underlying system you're configuring. Since there's a driver layer between the level 4 configuration and the system which can (ideally) be swapped out.