Assuming you want to set score=1
if any field is below 80, try this:
... | eval score = 0 | foreach count* [eval score = max(if('<<FIELD>>' < 80, 1, 0), score)]
Assuming you want to set score=1
if all fields are below 80, try this:
... | eval score = 1 | foreach count* [eval score = min(if('<<FIELD>>' >= 80, 0, 1), score)]
So you want a score of 1 if every count* field is less than 80?