Actually, his other exampkle with like is not correct either. Not at all! Why do you mark that as a helpful answer??? It's not helpful at all, just misleading, I am sorry.
The "in" operator has multiple operands at right-hand side.
The "like" operator suppports a single right-hand operand only.
And the upper function turns everything into uppercase,too. That will never lead to a match with lower case strings.
So what you can try is:
return lower($address) like '%ave%' or lower($address) like '%st%' or lower($address) like '%rd%' or lower($address) like '%blvd%' or lower($address) like '%dr%';
But beware! This is not a good use case for Information Steward. Values like 'First Orchard Square' will also Pass.