What you're quoting refers to the scaling of the axis after all the values are computed. This affects the numbers on the Y-axis, but not the shape of the graph.
The issue wting was raising is the definition of search volume. If search volume means "raw total number of searches", then the graph might support the OP's conclusion (if, e.g., we assume the population remained the same and that the same set of people aren't increasing the number of times they search for 'software consulting'). If, on the other hand, it means "fraction of all searches containing the term", then it might not because, as wting points out, the fraction of searches for 'software consulting' may go down due to a flood of searches for, say, 'honey boo boo'.