My xt came with one fitted however it was grey so I took it off over the winter to paint it up. Now I've never had the bike off road and there is no damage on the bike to suggest it's ever had a fall off road, one of the grey plastics on the side has a graze as if it's touched the wall but that's it.
On taking the plate off not only was there are crack at the same point as yours as split but along the front tube there was complete separation