Question: is 29 luggage considered oversized?
Answer: Many airlines limit the carry-on weight to 7 or 8 kg and it would be very, very easy to fill a 29-inch bag to be heavier than that. Easily allowed as a checked bag. Actually it is likely to be on the very limits of checked bag measurements which, for a lot of airlines, is linear 158cm / 62", so length + width + depth.