Mustrum_Ridcully
Legend
It's naturally difficult to classify.If it is the first few 4e books vs the core books of 2024 D&D, I think you could make the argument that 4e is simpler.
Right now 2024 D&D definitely feels wonkier at the table.
The base rules of 4E are fairly simple. But the exception based design of the powers (much like that of spells) adds a lot, and more importantly, during combat, the complexity rises because you have to consider the environment more, with all the area effects and position-changing abilities classes have. A combat on an empty plain, around a camp-fire, near a river, a cliff, on a bridge or a multi-room dungeon would likely play a lot more different then they would in 5e.
Then you have all the modifiers to consider.
DnD 5 combat modifiers are basically advantage, disadvantage, neither. Some of that is elegant, but for my taste it's too little in variety and too much in terms of effect, to be honest, but that's not a complexity issue.
DnD 5 has power bonuses, feat bonuses, untyped bonuses, some of them conditional, and combat advantage. (which is less than 3E with its phletora of typed bonuses).
And then there are all the conditions, and many reactive powers.

