Sure. The graph on its own doesn't prove causality. The graph, plus a little basic common sense, does give strong evidence of causality. Specifically, there's no other plausible alternative for the sudden dramatic turnaround in the mid-80s and sustained growth thereafter.
The turnaround in the mid 1980s predates privatization, so unless everyone had time machines back then, this is evidence against causality.
Also: common sense is not evidence. It never has been, nor will it ever be. Justification? Sure. Could even be that common sense is correct. But, evidence? No.
