Yes, I had only heared about him, but not in detail. But one thing you must keep in mind while commenting on somebody like Lalaji and tribute by his son. If you are not happy by the writing from his son, nobody cares. But one thing you must keep in mind is a person who has become President of FICCI must have achieved something in his life, and I am sure, your father was never or will never be FICCI President (otherwise, you will never make such abusive comment about Lalaji)
May be, anybody can claim that the article written is onesided giving only positive aspects of his personality, but I would ignore the negative aspects (even if some are there) as compared to what he has achieved in his life time.
You have to learn, to respect others and not to make any comment about anybody about whom you have never heard of.