Spiritual growth is there eversince. It is just that all of us differ in our awareness and priorities. It is a matter of hearing what you choose to hear, reading what you choose to read, seeing what you choose to see. It isn't really a sudden growth, spiritual advancement is already set. The thing is, as you mature, you gravitate towards your higher self and towards the same paths and issues together with others.
As the quotation goes 'nothing in life is permanent except change.' It is up to the person on how to implement the positives towards betterment; and those positives are mostly comprising of spiritual values.