I think LMGTFY is acceptable. Whenever I use it, I use it in jest. It also makes a point, that your answer could easily have been googled. It’s along the same lines as Google is your friend.
In my view, it does not qualify as “being a jerk”.
ETA: and note that whoever posts a LMGTFY link has actually made an effort to find the correct terms to search for that leads you to a satisfactory answer.
-xash
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