Great article!! Regarding the filters, I understand that the second code is more readable that the first one, but what about just put a better order in the filter:

people
   .filter(person => 
            person.age > 10 && 
            person.firstName.length > 2 && 
            person.lastName.length > 4
)

For me is just the same to understand than using 3 different filters. 😕

Thank you 😄