स्वभावो नोपदेशेन शक्यते कर्तुमन्यथा |
सुतप्तमपि पानीयं पुनर्गच्छति शीतताम् ||
Objects or people will always follow their innate disposition. It can not be changed by any amount of advice. No matter how much we heat water, left to itself, it will cool down.
-पञ्चतंत्र – मित्रभेद
And the only time frame window available to mold innate disposition of humans is Childhood to puberty i.e. Age 0 to Age 20. Once the innate disposition is fixed, it rarely changes. What changes you see are superficial, reflections of societal needs. Only way to change innate disposition after 20 is intense Sadhana which modern Indians refutes in their usual hurry.