The main angle is not to 'poisen' the training set. it is to waste time, energy and resources. the site loads deliberately slow and produces garbage, which has to be filtered out.
as i said: not a silver bullet. but at least some threads where tied up collecting garbage painfully slow. as the data is useless, whatever their cleanup process is, has more to do. or it might even be tricked into discarding the whole website, as the signal to noise ratio is bad.
so i would still say the author achieved his goal.