—“As a highly qualified and intelligent person, do you think that IQ can be increased and is it important?”—
Short answer “No”.
There is zero evidence that IQ can be increased and all evidence suggest it cannot, and it cannot because the seven or so factors that contribute to producing intelligence are genetically and developmentally determined.
HOWEVER, since intelligence largely provides an advantage in speed of accumulating knowledge, one can combine READING HISTORY, ECONOMICS and SCIENCE to improve your general knowledge.
General knowledge is the only substitute for intelligence. General knowledge of the general rules of the universe that science has taught us provides us with an unconscious understanding of how cause and effect are related at all scales. And economics and physics teach us that ‘nothing is free’.
In other words, benefit from the hard work of others in digesting the universe for you and then reading and understanding their words.
Is it important? The question is, you have a finite amount of life to spend. Do you need to spend it this way in order to improve some aspect of your life?