It´s a flawed post and arbitrary criterion. 0,33 in 45 is low I agree. But Eto so far 0,37 which is a also low figure. But he also did not play in 45 games but in 26 which is too few to rate him as a average striker. As people already noted, he shares his goals with other strikers and he will surely improve his strike rate by the end of the season.
How can Barca fans be so quick and, even worse, so happy to post wrong stats and pour trash on Barca legend is beyond me. But not so surprising when I see its more or less the same people who wax on Ibra 24/7.