Meaningless to some, the greatest wisdom for others,
Hence "platitude".
such is the quandary of relative knowledge.
What quandary? Either something is known or it isn't.
By "relative knowledge" I assume you are referring to opinion and assertion?
Baha'u'llah has given some interesting meditations on Knowledge, that I see is the highest possible standard of knowledge.
Circular reasoning. By what independent measure do you grade Bahaullah's writings as "the highest possible standard of knowledge"?
"..Knowledge is one point, which the foolish have multiplied...Bahá’u’lláh, The Ki tab-i-Ian, p. 183
If knowledge has been increased, how can those increasing it be labelled "foolish"?
". The source of all learning is the knowledge of God, exalted be His Glory, and this cannot be attained save through the knowledge of His Divine Manifestation..." Bahá’u’lláh, Tablets of Bahá’u’lláh, p. 156
Obvious nonsense. A huge amount of knowledge is gained through observation, experiment, evidence, rational thought and critical analysis. In fact, pretty much every practical advance has been made through this method. I'm struggling to think of any major advancement of human knowledge that has been gained through prayer and worship.
With all dues respect, your man sounds like he was making it up as he went along.
Abdul'baha, to me, gives us the best of thoughts, it is up to us to embrace, or not.
More question begging. If you could be a little more open minded and look beyond your narrow "Abdulbaha is best at everything in the world and I love him!" paradigm, you might gain some genuine knowledge.
". Is it not astonishing that although man has been created for the knowledge and love of God, for the virtues of the human world, for spirituality, heavenly illumination and life eternal, nevertheless he continues ignorant and negligent of all this? Consider how he seeks knowledge of everything except knowledge of God..." ‘Abdu’l-Bahá, Foundations of World Unity, p. 64
Considering that the majority of the population of the planet worships a god of some sort, your man would seem to be wrong again. Perhaps he just wasn't that "well-read" after all?
Yes, I know, meaningless platitudes to you
As you said earlier, some people find wisdom in meaningless platitudes. But they probably aren't using the standard definition of "wisdom" though.