There was topic dealing with “light forest” here:
The reason for the low density of trees was different there but the result to be seen OTG similar. To my understanding a forest area can well include some clearcuts without loosing the feature of being a forest. In my area I do not cut such places out of the area tagged as landuse=forest but just add the tag man_made=clearcut. As soon as trees cover the place again (like in your sample) I remove the clearcut tag and that’s it.
Anyhow if you want to take in the lower desity of trees I would think about tagging landuse=forest + forest=low_density or consider using scattered_trees=yes which was another proposal made in the quoted topic.