The ABS plastic is a fairly thin cover for a metal framework inside the stand, what size TV is it? Might be a factor as my old 5 series is only 32" so not exactly putting much force through the stand. Also, are the rubber feet okay, not uneven or visible out of place?
Yes unfortunately, the stand is not robust enough for a 50" screen putting cantilever force on it. Have you got a safety tether on the back of the TV to your entertainment unit? If not it would be wise to install one before the stand fails completely