One of the preset import rules, "[Campaign] Import >= 3 Orders & >= 80% ACOS as Exact", creates exact keywords for search terms with >= 80% ACOS.
This rule is in the "Sales Exact" strategic objective.
The reason for having an import rule to create keywords from high ACOS search terms is to optimize performance when used concurrently with negative rules.
In the above image, you can see that the strategic objectives "Sales Phrase" and "Sales Broad" contain negative rules that negate search terms with >= 80% ACOS.
Broad/phrase keywords can trigger search terms with high ACOS.
Moving them to an Exact ad group, brings the following benefits:
The broad/phrase keywords will be able to harvest more unique search terms.
The broad/phrase keywords can perform better without high ACOS search terms.
You can use bidding rules to optimize the high ACOS search terms/keywords to a more profitable level.