The most common and most likely answer to this crossword clue is the 13 letter word TECHNOLOGISTS
I've seen this crossword clue in The Times
T
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Buddy explains!

The straight part
We know that "IT workers" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case it workers = technologists.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does TECHNOLOGISTS mean?
TECHNOLOGISTS noun- A scientist or an engineer who specializes in a particular technology, or who uses technology in a particular field.